The bandwidth required for TV audio is much higher than it is for streaming just music, generally speaking. Which suggests you’ve got a borderline case of wifi interference , not enough to bother normal music streaming, but enough to get in the way when you’re doing the TV’s input. I’d look at that linked FAQ.

If that doesn’t help, then 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.

Thanks for the quick reply. Maybe that’s my best option but I guess my question is, why would this have just started happening out of the blue?  I didn’t change anything and it worked perfectly previously.  

Your network is affected by a ton of things, only a relatively small percentage of them are within your control.

My Sonos network went down as unreliable when a new neighbor moved in, and stomped on the frequency I was using for SonosNet. Took some investigation to figure it out, once I had, I change the channel I was using, and everything was fine. 

Even sunspots, which are on a a roughly 11 year cycle, can affect your wifi…along with dozens of other things. 

I’m making the assumption you don’t control sunspots….do you? If so, we need to talk :)