Originally Posted by captain_video
Are you using the HDMI output from the motherboard or graphics card? I know you can allow pass through of the audio when using a graphics card HDMI output, but I have no idea what you get from the motherboard HDMI output. Chances are you'll only get what you have configured in the sound device configuration on the HTPC. It sounds like you have the sound output configured as stereo and not 5.1 channels.
What are you using as your source? I'm confused as to how you are feeding the audio signal to the HTPC. I have no idea what you mean by stereo HDTV HDMI cable. The TV does not send audio back to the HTPC via HDMI. You need to provide a bit more information about your setup.
I got it working. I had to create a modified HDTV driver. That lets Nvidia driver put out dolby digital onto the HDMI cable.
I have an older no HDMI Sony AV reciever, an HDTV, and PC running windows 10 and a firetv stick and a HDMI switch with audioextractor.
Basically PC to HDMI switch with audio extractor, then onto HDTV, coaxial audio out on back of HDTV to coax audio in on reciever. The FIRETV stick is plugged into the HDMI switch
Here is my link with all the info.
Audio is not fed to the HTCP, the HTPC feeds audio out to the attached devices.
HDMI out is coming from the NVidia graphics card.
Now get this too, the Nvidia card has a display port and DVI port only. I use a PASSIVE display port to HDMI adapter, and that passes video and audio fine.
the HDMI switch I can have 4 input sources. And DD audio appears on both the switch coaxial port and out the TV coaxial port simultaneously. Really all I needed was a HDMI switch, not one that also has an audio extractor.