Sound, Kodi show 7.1 for 5.1 movie

Hi, i’m new on forum but use Kodi since Kodi 14.

Kodi developpers make awasome job.

I read a lot of posts on forum and search on web but i not realy have response for my case..

My config : W10 64 – Geforce Nvidia 730 (drivers updated) – HDMI to receiver Yamaha sound bar YHT-S401 – HDMI Out to TV.
Kodi 17 nightly build (08/1/2017). Same with 16.1 or 17 RC2.

Windows sound property config to 7.1

Kodi sound config with wasapi passtrough.

Sound is OK and Soundbar show DTS HD MA for a 5.1 Movie.

Movie info :

Audio #1
ID : 2
Format : DTS
Format/Info : Digital Theater Systems
Format profile : MA / Core
Mode : 16
Format settings, Endianness : Big
Muxing mode : Header stripping
Codec ID : A_DTS
Duration : 2 h 44 min
Bit rate mode : Variable / Constant
Bit rate : Unknown / 1 509 kb/s
Channel(s) : 6 channels
Channel positions : Front: L C R, Side: L R, LFE
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 spf)
Bit depth : 24 bits
Compression mode : Lossless / Lossy
Title : English
Language : English
Default : Yes
Forced : No

My question is : Why Kodi show 7.1 movie when played… (Batman – The Dark Knight Rises)
Why 8 bits when movie is 24 Bit depth

I’ try to config all in 5.1 in Windows and Kodi but same result.

Sound is realy OK but i ‘m asking why Kodi show 7.1…

If i use passtrough with Directsound HDMI, soundbar show PCM, sound is Ok too.
Kodi show 5.1

So, I do not notice any real difference in sound.

What do yu think ? Something bad configured ?

Thx. (sorry for my English)

LOG : http://paste.ubuntu.com/23763411