Curious as to what source you’re testing with. Just because the carrier is Dolby Digital doesn’t mean the content is. My local station, when they were carrying pre-season football games were sending me a stereo signal in a Dolby Digital wrapper, so I wasn’t getting a center channel or surround information. Not much Sonos could do with that. Sounded pretty odd, but since I root against the Cowboys at every opportunity....

It’s worth trying several TV sources and/or channels and apps, if it’s a smart TV, and double checking the settings on the device you’re using to feed the TV, as well. Sometimes, they can be off kilter. 

I’ve tried multiple streaming services and all act the same.

I’m using a roku ultra to an LG tv and the ARC to the Beam. The audio options for each device are set up for dolby digital. The system has been working but I’m not exactly sure when it stopped working.

Another thing that may be related to the problem is that TV Autoplay is behaving strangely. If I’m streaming a  music channel and switch on a video channel the music channel keeps playing with no video audio - the Audio In line in About My System is blank at this time. If I toggle the TVAutoplay selector from on to off and then to on the TVAuto play works as it should and the Audio In line in About My System is now set to Dolby Direct. The surround speakers still do not work though.  

Thanks for any help.

It’s not clear to me, based on your description, what the issue might be. At this point, 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, there are more options available beyond just the diagnostic analysis.

Oops. Which you have. I’d still recommend calling in with that diagnostic number, rather than waiting for a forum moderator to pick it up. 

After talking to technician he came up with a solution to my problem with no surround sound and a problem with TVAutoplay not working correctly.

Changing my LG TVs sound output from Auto (Dolby Direct) to PCM fixed both problems. I changed from S1 to S2 during the last few days so I don’t know if it is only an issue with S2.

Thanks again to tech support.