Best answer by Ryan S
As Jeff mentioned earlier:
This issue is specific to playing tracks or podcasts off of an iOS device using the "On this iPhone" or "On this iPad" feature within the Sonos app. We've found that playing off of the device can have audio cutouts, skips, or failure to play entirely, when the iOS device goes to sleep, or the lock screen comes on. With the issue we're investigating, it only comes up if you also have an AirPlay receiving capable (non-Sonos) device on the network, like an Apple TV. This also results in the Sonos iOS lock screen no longer working.
We're looking into it, but for now, the only fix would be to play the tracks or podcasts in another way, not off of that phone, or using AirPlay 2 instead if you have a Sonos One, Beam, Play:5 gen2, or Playbase. Alternatively, you could find the AirPlay capable device that's on your network and either isolate Sonos from it (by setting up a secondary network) or turn off AirPlay beaconing on that device.
If you're having cutouts on podcasts that aren't being played off of your iOS device or you're experiencing something else that isn't as described above, I'd suggest that you give us a call on our support line.
This is a pretty old thread, over a year now, and the original issue is unrelated to the iOS issue that we're working on. I'm going to close this thread for now, but we'll make sure to share in the main thread around the iOS issue when we have more information to share.