Sound just stereo instead of dolby when Play TV show

System: debian testing 64bit
TV: TVheadend (latest)
Reciever: Denon AVR1713
Setup: Computer is connected to Receiver and receiver is connected to the TV

I don’t know how I can describe this issue more clear than just with Kodi 17 the play back of tv shows are always in stereo. If i run Kodi 16.1 on the same computer and same TVheadend backend there is no problem with the sound at all.

Could someone share with me this behavior and/or give me a configuration solution to fix it.