Apple TV Outputting Sound to Rear Surround Channels with 7.1 Audio on Sonos Arc

  • 23 November 2020
  • 2 replies

Apple TV (4K) is outputting sound to (non-existent) rear surround channels when playing 7.1 LPCM audio on Sonos Arc.

The Arc should drop the extra 2 channels, or mix them into 5.1 output.

I’ve tested with movies on the Apple TV app and channel check files in Infuse on my LG B9 (eARC). This is persistent with all Multichannel PCM settings combinations.

2 replies

Edit: The Arc should mix them into 5.1 output and not drop the extra 2 channels like it’s doing now.

I’ve now replicated this issue on Xbox One X playing 7.1 LPCM test tones in Kodi.

Sonos specifically said they wouldn’t do this:

Similarly, Sonos says that Arc doesn’t “throw out” extra audio information that it gets from a single. For example, it only has speakers for five-channel surround sound rather than seven -- but the extra details in a seven-channel mix are mixed down to work in five channels rather than being left out completely.