I have a new Sonos Arc that will not play any sound from my Apple TV unless I restart the Apple TV.
Also with my XBox One I can only get sound to the Arc if I turn off my TV and turn it back on.
I notice that when I finally see the light flash green on the Arc then the sound (and remote) works again.
Never had these issues with the Playbar.
TV: Sony XBR-75X900E
Setup: Device → HDMI in on TV → HDMI ARC out to Sonos Arc
Suggestions to fix? Rebooting devices and TV to make the sound work is really annoying.