Didn't see anything like that here and not seen others reporting it.

You might want to call Support and have them look into it.

Thanks for the response - hoping that I’m an isolated case, and not part of a system update rollout.

There was a regular system update last week but Sonos do not brick their speakers.

Just because the app can’t find your devices is no reason to rebuild the system from scratch - your system is fine, its just the app isn’t reliable at finding devices.

You shouldn’t have rebuilt anything, just run the app again until it works properly, or use a third party app instead.

But where on earth might one find such a third-party app, ​@controlav?  

Why not disable Auto updates, and install when it suits you? 

Since last update 2 days ago my whole environment is pretty much bricked.  I am having speakers appear then disappear. I can’t group anything, it always gives errors or if I am lucky 1-2 speakers will play. I have had subs drop off them come back and it is a total sht show. We are a year past the absolute catastrophe of 2024 and yet here we are again.  I don’t know what it takes for Sonos to test their damn apps before roll out.  They are a fraud company IMO for the last year as their products are as reliable as a Tmu speaker. I have been a customer for a very long time and keep holding on, but I won’t play this game forever. I work in IT and know they can do better and I am also sick of hearing it is your network.  Nothing in my network has issues, but Sonos. All my Sonos worked 99.9% of the time until a year ago and my hardware for networking has not changed.  So sick of this Cadillac of a speaker providing acme level software for a reason/motivations yet to be disclosed. The whole cloud thing has always wreaked of data mining and a revenue move to me vs. keeping Sonos ecosystem living up to its claim to fame. 

I don’t recommend Factory Reset before working with SONOS support because diagnostic data will be lost. I don’t think that we can rule out a hardware issue with PLAY:3.