I recently got a Yamaha YSP 5100 Sound Projector. it supports all known formats of audio (from Dolby Digital to DTS MA 7.1)
It also support LPCM.
When I set the Apple TV to Best Audio Quality Available, and Infuse to Auto, any content that I have (MKVs, M2TS BluRay Rips),
that contains DTS or DTS-MA, I get only 2 ch instead of 7.1.
If I set infuse to Passthough - I get up to DTS and DTS ES 6.1 streams.
I also have an old PS3 connected that sends all its audio via HDMI to the YSP. the YSP Shows 8 LPCM channels perfectly.
(this PS3 release always sends LPCM via HDMI).
Any ideas what is going on here?