There are already many threads on this, it appears to be an issue on SiriusXM’s servers that feed your Sonos stream. SiriusXM doesn’t maintain a presence in these forums, you may want to contact them directly. 

Thanks, Bruce. Yes, I looked over the other threads before posting- similar problems but not quite the same. And I agree that most likely the problem lies with Sirius. However, the effect of lost channels is most likely to be registered here, within the subset of Sonos/Sirius listeners. And for my own research, it helps to know to what extent my issue is unique, or corresponds to others. Particularly in relation to the timing of the past couple weeks. The big question is whether the issue is programmatic and global, or local in nature.

Tom

I too noticed all the sports play by play gone. I can play them by asking Alexa to play a Sirius play by play station on a Sonos speaker and that works. But Alexa does disconnect after awhile. Not sure why.

Hey, Slip, that’s interesting: different things disappearing for different customers. I also have a Mixcloud issue on Sonos where only some programming returns a “connection lost” error. In the case of all these problems, though, it seems like it’s the station or program one listens to the most that has a problem. I’ve had many years of flake-free Sonos performance, but errors lately have really limited what I can listen to...

Like other Sonos users who have posted about odd things happening with SiriusXM, the missing channels, those higher than channel 500, have all come back today. So there was a period of 4-5 days that they were out. I did not contact Sirius; for whatever reason they came back on their own.