I currently have a Samsung LED DLP, Pioneer Elite SC-07 and Xbox One X. I do all media through the Xbox One X. TrueHD and DTS-MA from blurays comes through on the receiver fine and all channels are playing.
Using test demo MKVs with TrueHD and DTS:MA, I cannot seem to make the receiver say anything but some form of Dolby Digital. Take for instance the most simple DDTrueHD 7.1 channel check. When played and it cycles around the speakers and gets to the back left and right sounds, it just plays them in the Left or right sounds.
Even when I cycle through my AVR sound settings, still outputs DD. For example, even when I am in Stream Direct (which takes out my MCACC calibration, I still get Dolby Digital on those clips. Doesn't matter if it's a DD or DTS clip I am playing, still says DD. I have 2 media servers I am playing these clips from (PLEX and Serviio) and 2 different app players on xbox (PLEX and the MS Media Player). All servers and players exhibit the same Dolby Digital on the AVR.
Is there something I am not doing in either my AVR, Xbox One X or media servers that are not allowing these codecs to pass from an MKV file? Could something be set somewhere that takes whatever comes in and converts down to Dolby Digital?
These are the Xbox audio settings that I have: https://imgur.com/gallery/euK2abC
Changing to LPCM didn't make those channels work either.