Samsung and Sonos and Apple TV

HI,

I currently have 4 tv's set up with a Sonos soundbar - 2 Samsungs (Arc and Beam) and 2 LGs (both beams)

We have no issues with the sound on the LG sets but The Samsungs sound will not come on for several minutes sometimes as many as 10. I read the solution to set the audio output on the Apple TV to the TV speakers. I don't get this option....just receiver speakers. Is there anything else I could try?