[HN Gopher] Diagnosing an Unusual WiFi Issue (2020)
       ___________________________________________________________________
        
       Diagnosing an Unusual WiFi Issue (2020)
        
       Author : llimllib
       Score  : 252 points
       Date   : 2025-01-02 16:42 UTC (1 days ago)
        
 (HTM) web link (ryuuta.net)
 (TXT) w3m dump (ryuuta.net)
        
       | Johnny555 wrote:
       | >First, I purchased a new, highly-reviewed, wifi adapter on
       | Amazon.
       | 
       | This is not how you find a high quality product on Amazon.
       | 
       | >It didn't resolve the issue. It did, however, come with an offer
       | for a free 64GB flash drive in exchange for a good reviews.
       | 
       | Now you know why it was so highly reviewed.
        
         | Semaphor wrote:
         | > Now you know why it was so highly reviewed.
         | 
         | I'm relatively certain that was indeed what the author meant to
         | imply.
        
           | generalizations wrote:
           | Usually, you can see a few comments mentioning those offers
           | when you check the reviews. Amazon lets you go see just the
           | 1-star reviews; this is a good use for that feature.
        
             | jchw wrote:
             | It's interesting how it's actually really easy to notice
             | this happening as a random consumer (I've seen it a few
             | times, in fact) but somehow impossible for Amazon to do
             | anything about, and presumably when they do they don't
             | bother putting in much effort to properly punish sellers
             | for it. It's almost like Amazon does not give a shit.
        
               | PaulHoule wrote:
               | Part of my falling out with AMZN was when I saw a product
               | listing that where somewhere between fraud and word
               | salad, complained, and was told that AMZN doesn't care
               | what I think about a product listing unless I bought the
               | product.
               | 
               | Problem is if I try to buy something on AMZN I need to
               | sift through large numbers of junk product listings, a
               | problem I don't have with best buy, petsmart, adorama, or
               | other reputable online retailers. Even the marketplaces
               | like Ebay, Etsy and Temu seem less offensive to me.
               | Result = I canceled my Prime subscription and now AMZN is
               | the last place I will go to buy something and not the
               | first.
        
               | radicality wrote:
               | I wrote another comment in the thread about it, but fyi
               | as of now mid-2024 giving out incentives (free items /
               | discounts / cashback etc) conditioned on a positive
               | review, is considered fraud and can be reported as such
               | on https://reportfraud.ftc.gov/ .
               | 
               | Next time I see such an offer in an item I order I will
               | definitely report it. Maybe it will improve the online
               | shopping landscape by an epsilon if we all do it.
        
             | dotBen wrote:
             | Fakespot is not infallible but a useful addition to any
             | Amazon research process.
             | 
             | They try to hide it from the front page (a bit of a dark
             | pattern) but you don't need to download the plugin to use
             | it, just visit https://www.fakespot.com/analyzer
        
               | frereubu wrote:
               | Yeah, I was really annoyed when it to me quite a while to
               | find that URL after they changed the layout of the site.
               | I only shop on Amazon when I absolutely have to, and have
               | an extension just sitting there being regularly updated
               | with who knows what code really didn't appeal.
        
               | 0x2a wrote:
               | Bookmarklet:                 javascript:void(open('https:
               | //www.fakespot.com/analyze?url='+encodeURIComponent(locat
               | ion.href)))
        
             | radicality wrote:
             | If you are ever a recipient of such an offer (free item,
             | cashback, any benefit) and it is conditioned on writing a
             | positive review (ie giving 1/5 won't get you the free
             | gift), this is as of recently not allowed and considered
             | fraud.
             | 
             | Should report all such new cases you see to
             | https://reportfraud.ftc.gov/
             | 
             | ftc press release: https://www.ftc.gov/news-
             | events/news/press-releases/2024/08/...
        
       | cf100clunk wrote:
       | Just go right to the tl;dr
        
         | xattt wrote:
         | Good advice for all product reviews and most articles too.
        
           | cf100clunk wrote:
           | Anyone know of a browser extension that opens pages right to
           | any detected tl;dr headings?
        
             | reaperducer wrote:
             | If you have Safari, and a machine that supports Apple
             | Intelligence, that sort of thing is built in.
             | 
             | Click on the leftmost icon in the URL bar, select Show
             | Reader, then click on Summarize.
        
               | aruggirello wrote:
               | Mozilla's new Orbit AI assistant for Firefox is in beta,
               | BTW:
               | 
               | https://news.ycombinator.com/item?id=42555440
        
               | ppp999 wrote:
               | Apparently not available for Firefox for Android
        
           | fortran77 wrote:
           | No, it was very interesting to learn about his process and
           | the tools used to diagnose. (I had a similar problem with
           | Acronis True Image killing KiKad performace on Windows!)
        
             | cf100clunk wrote:
             | As I replied elsewhere, the process is often a joy to read.
             | In this case, perhaps a title like "Debugging QT5-related
             | WiFi Dropouts in Windows" would have been better.
        
         | sdflhasjd wrote:
         | Hackernews isn't a problems & answers forum, the process is
         | just as important as the conclusion.
        
           | cf100clunk wrote:
           | Agreed, the process is often a joy to read, but IMHO this
           | article was like one of those joyless vids or AI-generated
           | articles in which one must bulk scroll or fast forward to
           | finally get to the goods.
        
             | Andoryuuta wrote:
             | Haha, this made me chuckle :)
             | 
             | I'll concede on the joylessness front. However, I assure
             | you that all the posts on my personal blog are 100%
             | artisanal human-made joyless posts! No AI needed.
        
               | cf100clunk wrote:
               | Thanks, it was nothing personal. :)
        
       | Johnny555 wrote:
       | I was certain that I read about a very similar issue here in the
       | past, and after some searching, found this exact article posted 2
       | years ago:
       | 
       | https://news.ycombinator.com/item?id=32524702
        
         | cf100clunk wrote:
         | Algolia Search and Refined Hacker News appear to treat title
         | strings as case sensitive, so didn't highlight the original
         | version...
         | 
         | i.e. Unusual vs unusual
        
           | Raed667 wrote:
           | Not sure what you mean about the search? I managed to find
           | the post from 2022 with no issue: `rEsOlViNg aN UnuSuaL WiFi
           | isSUe`
           | 
           | https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que.
           | ..
        
             | cf100clunk wrote:
             | Now try using this url string Algolia Search:
             | 
             | https://ryuuta.net/blog/diagnosing-an-unsual-wifi-issue/
        
               | Raed667 wrote:
               | OK i see what is going on, the 2022 post was a different
               | URL that now redirects
               | 
               | https://blog.ando.fyi/posts/diagnosing-an-unsual-wifi-
               | issue/
        
         | Andoryuuta wrote:
         | Yeah, I should probably update my Hugo theme to include the
         | date (not that I ever write anything on there anyways TBH).
         | Also, the I changed domains not too long ago, so that probably
         | added some more confusion.
         | 
         | I wrote this in 2020 apparently:
         | 
         | https://github.com/Andoryuuta/website/blob/b95a693c745688995...
        
       | creeble wrote:
       | Interesting - Anyone know if this problem affects QT5 under
       | Linux?
       | 
       | I'll have to do some digging to find out, but curious if anyone
       | else has seen this on Qt.
        
         | TonyTrapp wrote:
         | It doesn't look like that polling code was used under Linux.
         | The fix was to only poll on Windows XP, since apparently this
         | wasn't even needed on newer Windows versions. The bug was also
         | fixed in 2018, so you would only be affected if your
         | distriubtion ships a severely outdated Qt5 version.
        
           | creeble wrote:
           | Thanks so very much!
        
       | 404mm wrote:
       | This is very similar to an issue I battled for months on MacBook
       | Pro (one of the later Intel versions, like 2018-ish), although
       | there problem was not in the HW itself but the current version of
       | MacOS at that time (this is no longer an issue).
       | 
       | I noticed that my WiFi had similar repeating lags .. about every
       | 8-10s pings would go to a few hundred ms and then return to
       | single/low double digits.
       | 
       | Long story short, the problem was with several MacOS components
       | (and maybe some 3rd party software) requesting Location services
       | to determine Mac's position. To do that, among other things, Mac
       | scans WiFi around you (probably for the names/SSID?) and to do
       | that, the current WIFI connection is temporarily put on a back
       | burner, resulting in a brief delay in traffic. The solution was
       | to minimize location services.
        
         | tonymet wrote:
         | This plagued a lot of remote workers when the trend started due
         | to ping latency causing terrible VC quality like delayed speech
         | , dropped frames, out-of-order frames . Very frustrating.
        
         | Suppafly wrote:
         | >and to do that, the current WIFI connection is temporarily put
         | on a back burner, resulting in a brief delay in traffic.
         | 
         | I can't believe they ever thought that'd be a good idea.
        
           | cenamus wrote:
           | Probably have to sweep across the frequency bands, so it's
           | physically the only way to do it. Still stupid to do it more
           | than once every 15 minutes
        
             | wbl wrote:
             | Fast switching on a background schedule while packets
             | continue to flow but at slightly reduced rate should be
             | possible. Might be very export controlled though given
             | obvious application.
        
               | gtirloni wrote:
               | You mean the RF circuitry has to continue working in the
               | frequency of the current network and switch frequencies
               | to scan for other networks in all bands simultabeously? I
               | don't think consumer hardware is capable of that. It
               | usually will send probes or listen passively for some
               | time in a band before moving to the next one
               | sequentially. It's an expensive operation.
        
               | wbl wrote:
               | I'm not an expert but I think depending on design this is
               | sacrificing one MIMO channel when active and adding
               | another PLL.
        
               | sitkack wrote:
               | It is more insidious to scan all the SSIDs within the RF
               | sightline of a device than it is to install a GNSS
               | receiver in the laptop. It means that not only do they
               | get all the SSIDs but that they have also triangulated
               | some of those SSIDs. You are also giving up the location
               | privacy of everything you can see.
        
             | gizmo686 wrote:
             | That's not the only way if you are the one designing the
             | hardware. Even if you can't make a radio that can listen on
             | multiple bands, you can add a second radio.
        
             | crest wrote:
             | Oh there is an obviously correct way to do it: have two
             | radios able to switch channels with without impacting
             | traffic, but that costs more money as well as space and
             | power. No lets just retrofit this crap into existing
             | drivers and hope nobody expects their computer to work
             | reliably.
        
         | bandrami wrote:
         | This is a great example of good ideas destroying themselves.
         | "Software should occasionally be able to find out where the
         | computer it is on physically is" is a cool idea, but once it's
         | there every single piece of crapware out there does it
         | constantly.
         | 
         | See also desktop notifications for websites
        
           | leptons wrote:
           | There's a big difference there.
           | 
           | You install an application you are giving it permission to do
           | practically anything it wants to do with your system,
           | including find the location as often as it wants to.
           | 
           | Browsers have to ask you permission to show desktop
           | notifications, or get your location, or anything else.
        
             | gtirloni wrote:
             | > You install an application you are giving it permission
             | to do practically anything it wants to do with your system
             | 
             | Not on macOS, AFAIK. You can add/remove permissions for
             | that.
        
               | eric-hu wrote:
               | This is a more recent feature. I'm not sure if such
               | granular permissions were in macOS back in 2020 when this
               | blog post was written.
        
               | bandrami wrote:
               | Even when you have granular permissions, though, it just
               | means the negative UX of having to click "no" every three
               | minutes because some jackass at Adobe is convinced you
               | really want to be told RIGHT NOW about every single
               | product they make (or whatever).
        
               | crest wrote:
               | The authorisation prompt doesn't show up once you denied.
               | Which makes sense to avoid user fatigue, but is annoying
               | when users denied it the first time (aka "go away stupid
               | modal dialog") and now complain about things working (or
               | not) as designed. At some point operating systems and
               | browsers will have to run a simulation to provide
               | realistic fake responses from denied subsystems if
               | application developers get even more brazen violating
               | user interests and maybe even *locally* analyse API call
               | patterns for abuse with the option of sending a trace to
               | make a claim against the developer with the application
               | distribution channel. Oh you added a bunch of criminal
               | spyware libraries praying on your paying users? Guess
               | that's a push notification to your whole install base
               | offering them a refund and a ban on further sales until
               | you've paid up. Except no existing player wields that
               | much power and can be trusted to use it wisely. _sigh_
        
           | jojohohanon wrote:
           | I think they should (permission allowing) be able to ask for
           | location, as often as they like.
           | 
           | I pin the system disruption from this query squarely on the
           | OS. It should make such determinations in the background and
           | return whatever value it has, without starting up a new scan
           | just for this query.
        
         | saagarjha wrote:
         | Reminded of https://mnpn.dev/blog/airplay-network-disaster,
         | which was a very similar issue (now resolved).
        
         | magic_smoke_ee wrote:
         | In recent times, I found 2 troublesome issues: one was network-
         | side and another was client-side.
         | 
         | 1. Google/Nest WiFi mesh APs being "too close" to each other
         | (30 ft / 10 m), causing a periodic backhaul mesh collapse.
         | There was no user-visible indication of this, it was completely
         | locked away and only noticed by support. I ditched Google's
         | junk and moved to Ubiquiti.
         | 
         | 2. On macOS, ObjectiveSee's LuLu has nondeterministic packet
         | loss that causes SSH connection resets and a whole host of
         | other weird problems. It's totally untrustworthy and shouldn't
         | be used by anyone until it's proven reliable.
        
           | ycombinatrix wrote:
           | Packet loss is supposed to be deterministic?
        
         | dlenski wrote:
         | > To do that, among other things, Mac scans WiFi around you
         | (probably for the names/SSID?) and to do that, the current WIFI
         | connection is temporarily put on a back burner, resulting in a
         | brief delay in traffic.
         | 
         | Scanning for nearby WiFi access points with excessive frequency
         | might be a dumb idea for other reasons (e.g. power consumption)
         | but it should *not* interrupt the functionality of the current
         | network connection.
         | 
         | If it does, that's a massive failure of the network card's
         | firmware and/or OS drivers for it.
         | 
         | My guess would be that the card is changing frequencies/bands
         | to scan other channels, and is slow to switch back to the
         | channel of the currently-associated AP, or doesn't properly
         | buffer network packets while doing so.
         | 
         | Under Linux, I don't think I've ever seen a case where WiFi
         | scans appreciably affected a normal infrastructure-mode WiFi
         | connection (whether from NetworkManager or triggered manually
         | via `iw` etc).
         | 
         | So much for Apple's vaunted hardware/software integration
        
           | vel0city wrote:
           | I've seen a lot of people experience lag spikes in Linux when
           | software scans for SSIDs. It's a pretty common issue overall
           | regardless of the OS, it's more of a device and driver
           | quality question.
           | 
           | https://www.reddit.com/r/linux_gaming/comments/3xipom/how_to.
           | ..
        
             | dlenski wrote:
             | > It's a pretty common issue overall regardless of the OS,
             | it's more of a device and driver quality question.
             | 
             | Right. I suppose I've been both lucky, as well as
             | intentional in seeking out hardware with high-quality
             | drivers when it was very important.
             | 
             | I'm just surprised that *Macs* have this issue, given that
             | one of the alleged selling points for Mac is that it runs
             | on a very limited set of hardware which is supposed to
             | enable careful OS/hardware integration and testing.
        
           | dehrmann wrote:
           | > Scanning for nearby WiFi access points with excessive
           | frequency might be a dumb idea for other reasons (e.g. power
           | consumption) but it should _not_ interrupt the functionality
           | of the current network connection.
           | 
           | Scanning works by tuning the radio to listen for a beacon
           | sent by the AP every ~100ms on every channel (there are 11
           | 2.4 GHz and ~22 5 GHz channels in the US). Since you're not
           | transmitting, it should be low-power, but you have to tune
           | the radio to each channel, so you can't communicate with your
           | AP.
        
             | dlenski wrote:
             | > Scanning works by tuning the radio to listen for a beacon
             | sent by the AP every ~100ms on every channel (there are 11
             | 2.4 GHz and ~22 5 GHz channels in the US).
             | 
             | Yes, but good drivers can mitigate the latency hit by not
             | scanning all the channels at once.
             | https://blogs.gnome.org/dcbw/2016/05/16/networkmanager-
             | and-w....
             | 
             | > Since you're not transmitting, it should be low-power,
             | 
             | Depending on the hardware/firmware quality, tuning to each
             | channel can use a lot of energy. As for "not transmitting,"
             | this is true for passive scanning (generally preferable)
             | but not for active scanning.
             | 
             | > but you have to tune the radio to each channel, so you
             | can't communicate with your AP.
             | 
             | Right, but _if the OS and drivers are written properly_ (on
             | both the client device as well as the AP ) they'll buffer
             | unsent packets... the high latency during the channel
             | changes is unavoidable, but the dropped packets and broken
             | TCP streams are NOT.
        
               | vel0city wrote:
               | From your quote:
               | 
               | > With a good driver scanning takes only a few seconds
               | 
               | A few seconds of not transmitting or receiving packets.
               | This is in line with people having sudden several hundred
               | millisecond ping spikes.
               | 
               | A few seconds of no real traffic is absolutely noticeable
               | impact for constant, latency sensitive traffic.
        
               | dlenski wrote:
               | > From your quote: > > With a good driver scanning takes
               | only a few seconds
               | 
               | You omitted the immediately following text: "*and the
               | driver breaks the scan into chunks*, returning to the
               | associated access point's channel periodically to handle
               | pending traffic."
               | 
               | A good driver will return to the AP's channel _during the
               | scan_ so that there is never more than (say) 100 ms of
               | latency even while the scan is ongoing.
        
       | xp84 wrote:
       | Worth the read just for the delightful Gift Note from your
       | brother. LOL.
        
         | fullstop wrote:
         | I'm glad to see that I'm not the only one sending and receiving
         | notes like this with my siblings.
        
       | tonymet wrote:
       | I encourage techies to dig into their wifi hardware & software
       | end-to-end. Install smokeping on a raspberry pi (even a $10 zero
       | works). Ping all of your home devices , your gateway, DNS & first
       | hops of your IP.
       | 
       | You will discover all sorts of disruptions affecting your network
       | quality, including interference.
       | 
       | For your primary devices like desktops & laptops, use mtr (my-
       | traceroute) in a terminal window to watch your pings over time.
       | 
       | Your connectivity issues , particularly with VC, terminal
       | emulation & gaming, are due to ping latency , not bandwidth
       | issues.
       | 
       | You will find software issues like this one, the location
       | services bug on MacOS, and others; as well as hardware issues due
       | to transmission interference, noise, physical interference.
       | 
       | Consistent & low pings are critical.
        
         | toast0 wrote:
         | This is such a pain to do though, because so much of it is
         | seeing braindead behaviors and not being able to do anything
         | about it.
         | 
         | Putting as much as you can on wired ethernet helps a lot. Still
         | have just as much bogus traffic, but on 1g (or even 100m),
         | there's a lot more room for it.
         | 
         | Everyonce in a while, I look at the broadcast traffic on my
         | wifi and cry.
        
           | tonymet wrote:
           | wired is best, but for many it's not possible.
           | 
           | MTR is a good start, and easy to run on a chron job. Graph
           | the results with excel
        
             | wolrah wrote:
             | > wired is best, but for many it's not possible.
             | 
             | For some it's not possible, but in my personal experience a
             | lot of people who "can't" wire really just don't want to
             | wire.
             | 
             | Even if you can't do a full "professional grade" install
             | there are almost always viable options unless you live in
             | an apartment built like a prison.
             | 
             | I have in the past:
             | 
             | * Poked tiny easily-patched holes in the wall just large
             | enough to pass a bare cable through to an adjacent room
             | 
             | * Tuck cables under baseboard molding
             | 
             | * Run cables through vents
             | 
             | * Followed existing television/telco wiring
             | 
             | * (last resort) Just stapled the cable to the wall/ceiling,
             | optionally covering with stick-on covers.
             | 
             | Most of those options can be hidden from view and all are
             | trivially removable/repairable so there's no issue in a
             | rental situation.
             | 
             | Almost everyone can do most if not all of those things if
             | they want to, they just usually don't want to because
             | they've been trained to not like wires, that wireless is
             | better.
             | 
             | I have actually had a person complain about lag on their
             | game console, which was in the shelves under their TV
             | connected via WiFi to their cable modem which was in the
             | same shelves, and they didn't want me to plug in a simple
             | six foot cable between the two because they didn't want
             | more wires. That's just pure stupid.
             | 
             | If it doesn't move, it should be wired unless there is
             | absolutely no practical way to wire it. Desktop computers,
             | game consoles, TVs, etc. Even laptops, if you're working
             | from home and sitting at a desk, have a cable there. Modern
             | laptops with USB-C docking stations make it easier than
             | it's ever been, the same cord that provides power also
             | provides reliable high speed networking.
        
               | tonymet wrote:
               | fair enough. You're right it is possible. To me it's not
               | worth the unsightly cabling and damaging penetration. I'm
               | currently measuring about 1.5 ms / 0.5 ms SD pings on
               | wifi. I could save 1.0ms on that by running cat5 around
               | my house. But it would be unsightly , and add more
               | penetration through my walls.
               | 
               | It's all about tradeoffs. My efforts spent on running
               | great wifi have paid off.
        
               | wolrah wrote:
               | Best case vs. worst case is important.
               | 
               | Best case, yeah WiFi isn't substantially worse than
               | wired, especially if all you care about is getting to the
               | internet. Worst case, it's a fuckton worse. A wired
               | network will never drop out for seconds at a time because
               | something ran a scan (as noted in multiple places in this
               | thread). A wired network doesn't give a shit about your
               | microwave. A wired network doesn't have meaningful
               | interference issues.
               | 
               | The more active users you have on your network, the worse
               | WiFi is going to be, where a wired network can take more
               | users than you can fit in a residential environment.
        
               | tonymet wrote:
               | that's not "best case". that's a 30 day reading.
        
               | luma wrote:
               | For whatever it's worth, running cables through your
               | vents in the US is an NEC violation (see 300.22). If
               | you're renting it might be your only feasible option but
               | probably not a great long term solution.
               | 
               | Otherwise, I strongly agree with everything said above,
               | wired networking is worth the investment.
        
               | wolrah wrote:
               | AFAIK low voltage wiring generally doesn't matter from a
               | code perspective, but yea I would only see that as a
               | temporary solution for renters and of course only use
               | plenum-rated cable for it.
               | 
               | I've only done that particular trick in an apartment that
               | had through-wall vents above the bedroom doors so it was
               | literally four inches the cable was inside the vent.
        
         | creeble wrote:
         | Good advice, but I'll add that there are many bad things
         | smokeping won't detect.
         | 
         | My favorites are APs/range extenders/meshes that don't do
         | multicast properly (mDNS in particular, breaking lots of LAN-
         | based apps), and also ones that seem to semi-randomly isolate
         | devices (i.e., prevent devices connected to the AP from
         | reaching devices that are not connected to it, except the
         | gateway).
         | 
         | There are a huge number of these devices (I'm looking at you,
         | Netgear). Sometimes ICMP will work, but not TCP. It's
         | nightmarish to debug, because it often seems to be some table-
         | size issue in the AP, so devices will work for a while, and
         | then some new device connects and the old ones break.
        
           | tonymet wrote:
           | you could use nmap or tcpping as the probe . smokeping
           | supports any diagnostic
        
       | settsu wrote:
       | TFA never addresses what MediBang Paint Pro is using Qt for.
       | Checking for updates, etc. (e.g., online account connection,
       | sharing)?
        
         | mrgaro wrote:
         | As Qt is a GUI library (among other things) I would guess that
         | Paint Pro is written entirely using Qt.
        
           | settsu wrote:
           | Ah okay, forgive my ignorance. The way the article is written
           | I interpreted it to be a library.
        
             | dgfitz wrote:
             | I have a love/hate relationship with qt. It is powerful,
             | generally well-maintained, and I've compiled the same app
             | to windows, linux, Mac, and arm, and a specific use case
             | needing JNI on android.
             | 
             | It all just worked.
             | 
             | Their licensing got really goofy for a while, and yocto
             | (which unfortunately I became a "SME" of at work) made
             | cloning and using anything after 5.15.2 very obnoxious.
             | They needed to figure out how to pull a RedHat and get paid
             | support, but this was right around the time electron (at
             | least for a while) rendered native apps as second-class
             | citizens.
             | 
             | The bindings to other languages are neat, and the
             | signal/slot idea is also neat. The whole moc part isn't
             | great, but I understand why, and it has very rarely caused
             | me any real issues.
        
       | can16358p wrote:
       | I have a completely unrelated issue: since switching to a new
       | iPhone, only my iPhone occasionally can't access anything on Wi-
       | Fi.
       | 
       | All my other devices, including a MacBook and iPad connected to
       | the same network work fine. My previous iPhone also worked just
       | fine, it's just the new phone.
       | 
       | I know how annoying these can become, and glad to hear that you
       | could pinpoint it down.
        
       | cyberax wrote:
       | I had a similar issue!
       | 
       | Around 2017 I moved into a new house and my MacBook Pro started
       | getting latency spikes every few minutes. Not as bad, but still
       | noticeable. This irked me quite a bit, because I spent several
       | weeks wiring my house with the best POE-powered WiFi access
       | points available at that time.
       | 
       | So I spent some time debugging the issue, and it turned out that
       | the culprit was in the location services! For some reason, the
       | weather widget tried to check the location every few minutes, and
       | that involved scanning for the WiFi access points. Which in turn
       | meant that latency spike, I posted about it on StackOverflow (
       | https://superuser.com/questions/1142798/experiencing-high-la...
       | ).
        
       | deathanatos wrote:
       | But why does querying the registry cause the WiFi to drop?
       | 
       | It smells like there is a AP search occurring, which I think
       | usually causes the antenna to frequency hop for the duration
       | search, which results in latency on the established connection
       | since it can't transmit at the same time.
       | 
       | But does enumerating registry keys do that? I didn't think the
       | registry had dynamic behavior like that.
       | 
       | Still ... a ridiculous bug.
        
         | rincebrain wrote:
         | If I understand correctly, it's triggering an actual wifi AP
         | scan, and the AP enumeration in the registry is a side effect
         | of finding the interface to go ask it to rescan.
         | 
         | But I might be missing something.
        
       | j-scott wrote:
       | This is very similar to an issue I had while playing games on a
       | wired Windows desktop. I haven't run into it in a long time now
       | that I think about it. I wonder what might have changed.
        
       | rincebrain wrote:
       | My favorite stupid wifi thing I ever had, for some value of
       | favorite, was a previous incarnation of my home router, which
       | apparently had a known issue where certain Intel wifi cards
       | connecting to the AP would cause it to start having firmware
       | crashes randomly, which I discovered when I brought home a new
       | laptop and my wireless on every device started being
       | unreliable...
       | 
       | Nothing to be done about it other than "don't do that" or
       | "replace AP" since the firmware is a black box. It
       | was...maddening.
        
         | apfsx wrote:
         | I had this exact same experience with a brand new Dell XPS 15 I
         | purchased around 2018 I believe. It came with a killer branded
         | Wi-Fi card and I noticed shortly after purchasing that it would
         | literally bring down my entire home network at the time. I
         | don't remember what router I was running or the rest of my home
         | network set up at the time, but it was definitely a really
         | bizarre thing to witness, I ended upreplacing the Wi-Fi card.
        
       | foldor wrote:
       | On a related topic. I have a really weird problem in my house
       | where I'm about 20 feet from my TV trying to use my PS5 DualSense
       | connected to a Google TV device connected behind the TV. It uses
       | Bluetooth, which is also 2.4GHz, and the issue I'm having is that
       | the dongle behind the TV is really impacting my controller
       | connection and making playing games over PS Remote Play
       | completely impossible. I even have the GTV device hard wired with
       | an Ethernet adapter, as is my PS5. This can't really be a range
       | limitation can it?
        
         | EvanDotPro wrote:
         | (Obligatory HN pedantry: arguably unrelated, but now I'll try
         | to help anyway because this is quite common.)
         | 
         | Bluetooth is pretty low power, but without the TV in the way,
         | that range should be no problem at all. Problem is that a lot
         | can block it physically and drown it out in RF noise.
         | 
         | Most TV's probably have a thin, but solid aluminum plate in
         | them for structure that could indeed block BLE and be causing
         | the issue. Ironically, this is one RF case where metal studs
         | would actually be helpful.
         | 
         | For comparison, I fly a paramotor and use Sena Bluetooth mesh
         | for comms, and just our heads at any distance are enough to
         | block it if we're on the wrong side of each other.
         | Motorcyclists on the other hand don't often have this issue
         | since there's other vehicles and stuff to bounce their signals
         | around.
         | 
         | What might help if that's the issue is something reflective
         | like foil mounted somewhere that can see both the controller
         | and the GTV device. I'd also try to make the reflector
         | slightly/roughly parabolic-ish (kinda shallow as to not make
         | aiming difficult) pointed at the GTV device. You can hide the
         | reflector behind and/or point it through anything RF
         | transparent like wood or plastic.
         | 
         | Another possibility is other 2.4ghz noise-- You could try
         | turning down 2.4ghz transmit power on your AP as a possible
         | quick fix. Of course if you haven't, make sure anything that
         | can be on 5ghz, is.
         | 
         | Edit: Note that a reflector will also reflect noise sources at
         | the GTV device.
         | 
         | I've also had issues with poorly shielded HDMI interfering with
         | 2.4ghz in close proximity, so even just jostling things around
         | behind the TV a little or using your best shielded HDMI cables
         | there could help some.
         | 
         | Debugging RF can be tricky and frustrating, but I hope one of
         | these tips helps either you or maybe a passer-by one day. :)
         | 
         | Happy new year!
        
       | garganzol wrote:
       | At last, I know what probably was causing my Realtek WiFi
       | problems during that era (circa 2020). It is so strange that a
       | Ring 3 application can wreck a havoc on the networking subsystem
       | for the whole OS. Also it is weird that Qt, being a UI library,
       | takes a role of advanced network guardian by monitoring the
       | activity of network interfaces. What a mess.
        
       | NotYourLawyer wrote:
       | > Later, (for unrelated reasons) I built an entirely new desktop
       | computer, not using anything from the old one, except the new
       | wifi adapter. This included a fresh install of Windows 10... A
       | few weeks later, and the issue suddenly began happening on the
       | new computer also
       | 
       | This pretty clearly points to some weird software you've got
       | installed. It's not hardware, and it's not a wonky Windows
       | installation. What else could it be?
        
       | Pxtl wrote:
       | My reaction:
       | 
       | "If scanning for wifi has that much negative impact on my
       | connection, the OS should by default pop up a toast notification
       | when it happens without a user request to do so."
       | 
       | If MS can put slop like news and weather and ads for apps like
       | Candy Crush into the Windows GUI, they can also give me _useful_
       | info like that.
        
       | tuzemec wrote:
       | I have a similar issue with two M3 MBPro machines. There's a high
       | volume of lost packets when I'm connected to my home 5GHz wifi.
       | The 2.4 connection works just fine.
       | 
       | All the other devices don't have any problems.
        
       | alcoholic_byte wrote:
       | I think some are missing the actual point here: Why does a
       | software/hardware/driver concerned with drawing need to know what
       | wifi-networks are available? That is tantamount to surveillance.
       | An absolute no-go.
        
       | disillusioned wrote:
       | This isn't even particularly close, but I had a gremlin that I
       | would notice at night time where I'd hear my CPU fan idly spin up
       | and the computer slow down... come to find out I was basically
       | getting port scanned and _blasted_ with RDP requests, and since
       | RDP is a nightmare protocol with no rate limiting to speak of, it
       | was obvious that some botnet had found the port I had changed RDP
       | to and was hammering it to try to gain access to my computer.
       | This manifested with svchost.exe maxing out CPU, and digging
       | deeper revealed it was coming from a botnet in... well, who knows
       | where.
       | 
       | Obviously that was all the incentive I needed to finally heed my
       | devops friend's warning and disable port forwarding and instead
       | use Tailscale for remote access, but yeesh. Wild to watch happen
       | first-hand.
        
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