HTPC to Xbox One input to Denon AVR-2100W outputs only 2.1 Stereo. Why?

Ok so I have searched and searched and searched for a solution and have found nothing. I am hoping someone here can help me out. My setup is a HTPC with 980 TI SLI to my Xbox One Forza edition input via HDMI, to my Denon AVR-2100W via HDMI, to my TV via
HDMI. I have gone through the settings on the xbox and changed the "display and sound" to Bitstream and I have changed the "Tv and Oneguide" to surround sound output. Xbox games play dolby digital just fine. HTPC only shows stereo as an option for audio
output. What am I doing wrong here that is limiting my HTPC to output 2.1? If I connect my HTPC directly to my Denon it will let me choose 7.1. Through the xbox it will not. All devices and firmware and drivers are completely up to date. What gives?

:)

 

Surround Sound Not Working

Ok, I found something. If I select "Stereo Uncompressed" in sound setting in Xb1, my AVR gives me the "Dolby PLII Movie" and "DTS Neo:6 Cimena" output options. Selecting this, I get output form whole 5.1 system, but the Input signal detected by AVR is only
a 2 channel input. I believe my Marrantz is taking the uncompressed stereo and converting it into 5.1 output. This is also the case with the videos I played back through chromecast. Is this pure surround or just a lot of sound from all the speakers.

In contrast, if I select 5.1 uncompressed in audio setting in XB1, the input is detected as 5.1, but output is only from front, center and sub. I am getting super confused.

 

XBOX One Audio Settings

I am having an issue with the Audio output. I will set my XBOX One to 5.1 or 7.1 uncompressed and it will stay set this way until the next time I turn my XBOX on. Then, it resorts back to Stereo. Hard shutdowns do not fix this issue.

I am running HDMI to a Denon AVR-991 receiver.

Does anyone have any ideas?

Thanks!

 

Still nowhere with this issue. For those of you who have an HTPC connected to your Xbox are you able to select 5.1/7.1 @ the configure screen on playback devices when you select the Xbox?