Anyone have any idea if possibly Amazon's devices could be doing the same thing? We were experiencing this same issue and at first thought it was the router, so we went and got a new one but still had the same issue. I do have a Google Chromecast, but it wasn't plugged in (HDMI nor power chord), but my daughter recently got an Amazon Echo Dot. She had been using it for a week at home with no issues, but then after New Years day, our router would start disconnecting over the WiFi (anything hooked up to it via a cable was fine). Just curious. Since she went back to school at college, the problem seems to have gone away.
I am wondering the same thing about the Amazon devices. I have an Echo and an Echo dot. They worked fine with my wifi for months but lately my wifi seems to have gotten a unreliable. I have 2 Chromecast, but neither has been plugged in for sometime.
This article doesn't make sense. The article says the TP Link Archer C7 (AC1750)is affected, but the patch link provided is for the AC1200 router. So, which one is it? The latest firmware for the Archer C7 is from July 2017, according to the TP link site.
All these articles are a bit misleading, or leave out the basic info that it seems to be the apps used to cast to the google devices, not the devices themselves, that are sending out so many mDNS packets they are choking routers. Specifically it appears to be apps on Android 7/8, that normally sent a query every 20 seconds, but when waking after being suspended, send all the packets they didn't while 'asleep', which can add up pretty fast.
If this is the case, and it seems to be the accepted explanation, I don't see how unplugging your chromecast or Home is going to solve anything. The android apps are still going to search your network for devices to cast to. I could also see how you could have issues without any Google devices, if you using the YouTube, Google Play Music, or other google apps with casting enabled. Seems like disabling the ability to cast on your Android devices, or in the apps would be the real (temporary) solution until Google updates them.