My Xbox One is connected directly to a 7.1 capable amp and set to output 7.1 PCM uncompressed. But frequently sound is output to the rear back speakers when it should be output to the side surround speakers.
For example Halo Master Chief Collection the game itself does output correctly to 7.1 but some cut scenes are 5.1 only. Which is fine, but the problem being the sound is being output to the back rears and the sides are dead, it should be the other way round.
Castle Storm is 5.1 only and the surround sound is only back rears (even after last title update) and I have to manually set to 5.1 PCM to correct it.
Digging around a few AV forums this is a problem inherent only with the Xbox One. I have no problems with my PS3 & PS4 playing 7.1 and 5.1 with correct speaker channel mapping.
The speaker channel output needs a firmware fix. Manually having to switch between 5.1 and 7.1 should not be necessary, and in the case of Halo which is "both", and the output is wrong. Highlights the issue.