Yes, I understand it’s an ongoing issue. I think the earliest report was this thread below, albeit it was originally confused with a slightly different issue, which Sonos resolved. Anyhow perhaps start here…

@mwhitworth65,

Just to also add, if you search online, that my understanding is that Samsung have had soundbar issues with some of their TV models going back some months now and they did think they had resolved the issues after a September firmware update, but some users reported that things were ‘still’ not fixed for them and this was with soundbars from a variety of different manufacturers (aswell as Sonos) - then came the Sonos 15.8 update and so it’s not entirely clear where the problems may lie, but some users do say that switching off eARC on the Samsung TV fixes the issue in most cases. 

Presumably Sonos and/or Samsung will get to the root cause and between them hopefully fix the issue. Meanwhile try switching off eARC on your TV and see if it resolves your issue temporarily, until a fix is released.

HTH

My sonos beam gen 2 disconnect from Samsung TV almost every time i switch off the TV for quite long time and turn it on again. The only way to connect sonos to TV after that is disconnect soundbar from the power and plug it again. I have spoken with Sonos and Samsung recently many times (tofay again with Samsung) and no help at all. Sonos says that the issue has been resolved with their last firmware update and my issue is some exception. I have tried so many things with the setings and with changing 4 different high quality HDMI new cables. Also not keeping any other HDMI cables connected apart of Sonos connected to eARC port... And same issue again and again. Samsung were useless also so far. 

I don't know. That's a shame