I have been playing games on Google Stadia over wifi for months without a problem. Since 8 am on 24 Dec, it has become unplayable (stuttering/pixelation). Here is some troubleshooting information:
1. I have a M350 broadband service.
2. Rebooting the router didn't help.
3. Google Stadia plays fine using a PC connected via ethernet (but that is very inconvenient).
4. Other apps/services (e.g. Netfix) still work fine over wifi.
5. Speed tests over ethernet look fine (390/40 mbps).
6. Speed tests over wifi vary with time of day (50-10 down/20-12 up).
7. The problem has persisted when I tested at 6am this morning.
8. A wifi ping test to google.com gave 30ms average round trip and 0% loss.
Any help would be greatly appreciated.
I have managed to figure out the issue myself. For some reason, my Hub 3.0 router had disabled the 5Ghz wifi band. Turning it back on fixed the problem.