In the past few weeks the vocal track of Dolby Digital 5.1 sound has been only coming out (loudly) of the left rear surround speaker of a Sonos Arc System. No voices come from the Sonos Arc, but it sounds like surround speaker sounds are coming from the Arc. So shows in DD 5.1 are basically unlistenable.
My system: 1) Sonos Arc/Sub/2 Sonos One surrounds, 2) LG CX 77 TV, 3) Apple TV 4K 3rd gen
I stumbled upon a fix, which is to toggle eARC off and back on again on the LG CX. After than sound comes from the Arc, but eventually this has be redone (see below).
Why is this happening and is there a better fix? This is a new problem that started a few weeks ago.
Further details:
- To play DD 5.1, I have to explicitly set Apple TV’s audio format to DD 5.1 because when you set it to “Auto, Atmos Available” you get Multichannel PCM 5.1 which sounds bad. This is a known limitation of Apple TV (https://en.community.sonos.com/home-theater-228993/apple-tv-unable-to-switch-dolby-formatting-with-arc-6869224 ). Voice correctly comes from the Arc with Multichannel PCM 5.1, but voice incorrectly comes from the left rear surround with DD 5.1
- My fix of toggling eARC on/off works, but when you change Apple TV’s audio format to “Auto, Atmos Available” and back to “DD 5.1” then voice starts coming out the left rear surround speaker again. It’s a pain to have to keep doing this, but better than having to listen to lower-quality multichannel PCM 5.1 instead of DD 5.1
- Rebooting Apple TV doesn't help. Removing/reinstalling surround speakers in Sonos doesn't help.