I have a Bar, Sub and 2 Play 3s configured together. I've tried using the Sonos network ("WM:0") as well as my wi-fi network. I've tried changing the wireless channel. All to no avail, so at this point, I'm not sure what to try next. The Play 3 speaker drops happen intermittently with no real pattern and last about 10-15 seconds. The surround speakers re-join without any action from me. This happens when playing music from streaming services (Spotify) as well as music in my local library.
I'm actually using a fairly new router that has a very strong signal (Asus GT-AC5300), but the issue existed with my prior router as well. The affected Play 3's are within about 10-15 feet of the unobstructed router and hard-connected Playbar. I've done some channel analysis and made multiple updates to the channel the router uses for 2.4GHz (it was previously set to Auto) to no avail.
I've changed to static IP's for all the Sonos devices, recycled the router/modem, moved 2.4 GHz channels, etc. I followed suggestions I've seen in other threads here, but have ultimately also submitted a diagnostic - 7529177.