I know that this is not a coding question and I have posted on the regular Apple Forum and have been working with the 800 Tech Support folk for 4 months.
I am in a world of hurt.
Have ATV + Samsung TV + external soundbar.
All software versions are current
NO Cable box (direct input). 4 months ago I had Cable box = zero problems.
With Samsung on and ATV off, stereo = Dolby 5.1 sounds great.
With ATV also on, no stereo.
I can use Siri remote to activate stereo until I change to a new movie. ATV then reverts to mono = PCM
One Tech Support lady said to just not watch multiple movie.
?$@!*+^?
I have spoken with engineers at Samsung and Sonos (soundbar). Both say my cabling is correct = 1 cable from soundbar to HDMI Arc on TV + 1 cable from ATV to another HDMI port on TV.
Another Tech Support folk said to connect ATV to soundbar. Soundbars don’t have gobs of HDMI ports, the TV does.
?!$@*^+%#
I have spoken with Apple Tech Support with zero help for 3-4 months.
I think I have been a good soldier. But it is time for real results.
Please help
After 3+ months, I talked with Tim from Apple Support
Solution = disconnect your soundbar‘s HDMI cable going to the TV’s ARC port and connect it to non-ARC port.
RESTART ATV
My soundbar‘s Stereo components = sub woofer + surround sound wall speakers emit sound no matter how many different movies I switch between.
Reason = ATV has problems with the ARC port connected to anything in the ATV chain (which obviously includes the soundbar).