Without more details, it’s hard to tell, but I’ll guess that you may have some wifi interference that is affecting the connection between your speakers and the servers that feed them the signal. Enough to cause that error, at least. I’d recommend reading the linked FAQ, and also perhaps a network refresh, by unplugging all your Sonos devices from power, followed by a reboot of your router. Once the router recovers, you should plug in the Sonos devices, give them a few minutes to reconnect, and test again.
However, if this does not resolve the issue, I would recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it.
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 phone folks, they have tools at their disposal that will allow them to give you advice specific to your Sonos system and network.
