I have a standalone Play 1 in my bedroom that does not connect to my wifi anymore. It worked fine for years, the problem started when I changed my wifi from 2.4 Ghz to 5 Ghz, and then after back to 2.4 Ghz (because I learned Sonos does not work well with 5 Ghz).

The Sonos system in my living room is still working perfectly.

I tried everything to make it work again without result:

• unplug power and restart
• reset to factory settings
• connect with ethernet cable to update sofware 
• reboot my router

Everytime when I try to connect the Play 1 to wifi using the steps in the Sonos app, I get the same message: “we could not connect the play 1 to your wifi”.

The 2.4 Ghz frequency (active) and 5 Ghz frequency (inactive) have separate names in my router, so there can be no confusion in the system about that.

Thank you very much for your suggestions :)