Make sure that the TV’s Anynet is enabled. I recommend powering down both units for at least two minutes and removing all HDMI cables. After powering up BEAM and the TV, connect them with the HDMI cable. After they discover each other you can connect other devices, if any.

I think we've tried this. But will check and try again. 

Checked and yes Anynet is enabled, and  no the beam 2 does not show up as a sound source. The only way we can get it to show up, and to be seen on screen as volume + - (Sonos Beam - Hdmi eArc) is to unplug the beam, plug it in again and wait for it to reconnect to the network.  ZThen turn on TV and it's there. For all sources; PVR, called home cinema on Samsung, Chromecast, and Blu Ray player. Weird. Tx

I’d also double check for updates to the TV’s software, it sounds like it isn’t properly keeping a CEC connection. Would hurt to reboot the Sonos, for that matter, although I’ve never heard of one doing this, either. 

What’s the TV model number? 

Samsung qe55q80cat.  System on Sonos up-to-date.  Tv brand new and updated after installation. 

Found this dated  a month ago: 

There was a similar issue recently whereby Beams would have no audio when playing TV audio coming from certain Samsung TVs, which has now been resolved. As your TV and Beam seem to be losing the connection between them, however, this seems like a different issue. I recommend you get in touch with our technical support team who have tools at their disposal that will allow them to give you advice specific to your Sonos system and what it reports. 

Sounds like our problem too, same TV. Will try technical support. Unless any updated information from other users. Thanks 

This is an ongoing issue for a lot of people. I have a s95b and Gen 2 beam, which worked completely fine. Then 2 months ago it lost connection and I now have to keep doing a power down to reconnect. It’s an issue between Samsung and Sonos software updates but not thing is being sorted which is bit of a let down.

I have to reboot my Beam to restore the connection to my Samsung TV! It is driving me mad…I wish i had bought the Samsung speakers at a third of the cost. Any suggestions….

I’ve been on a live chat with Sonos this morning and they are aware of the problem and they say that the issue is trying to be fixed between Samsung and Sonos.

But there lies the issue Sonos and Samsung dealing with one and other. But probably saying it’s not from there end. Whether it gets resolved who knows. When it does work it’s excellent. So much living a world of smart technology, it’s too smart for its own good.

I’m of the opinion is that if it was a Sonos issue, it would be affecting more TV manufacturers than Samsung, and we’d see this problem cropping up all over. The fact that it isn’t certainly suggests to me that Samsung has messed with the CEC stack in some way, and needs to release a new version of their firmware to fix it. 

I this exact problem with a Panasonic TV - so my moneys on the Sonos.

CEC can be quite a mess. There are no ridged specifications with respect to how the units should interact with each other. When issues develop manufacturer ‘A’ blames ‘B’ and ‘B’ blames ‘A’. Eventually, if enough complains pile up ‘A’ might make a change. Hopefully, ‘B’ will not also make a change that negates the ‘A’ fix, but then ‘C’ might develop an issue.

Inserting a CEC blocker between the TV and SONOS might help. After inserting the blocker you’ll need to configure the TV and cable remotes to use IR for Volume control, then train SONOS to use IR. When you setup the TV and cable remotes, simply pick the same arbitrary home theater model number. (don’t use a model that is nearby)

Anybody aware of any progress on this problem? Are we still waiting for Sonia/Samsung to get their act together!!

I agree. Love the sound when it works but almost every time I turn off the TV I have to reboot the Beam. I like having the 4 Sonos speakers but this is driving me mad and I am sure Sonos knows about the issue and is just ignoring it. 

I had an answer for you over there…