Sounds like there’s some issue with your system maintaining a connection with the various stations. I’d certainly try a network refresh, which it seems you’ve almost done already, just missing the one key component.
Try unplugging all you Sonos devices again from power, then reboot your router. Give the router a couple of minutes to recover, then plug in your Sonos devices to the power again. Give them a couple of minutes to boot up and reconnect as well, then check for updates and apply them, and finally test your playback. .
This should fix your issue, however, if it doesn’t, I would recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it. Don’t post the resulting diagnostic number here, they get sensitive about GDPR.
There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.
When you speak directly to the Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.
