Not sure if this is just a configuration issue, or if it's a failure of the most up-to-date driver.
I have a HTPC setup. PC includes an ASUS MB with on-board video and audio, including options for either separated analog 7.1 audio out or HDMI out (among other output options). Current setup routes Audio and Video via HDMI to Pioneer VSX-1020 A/V receiver, and routes video from there to HDTV via another HDMI cable. OS is Win7 Ultimate x64, w/SP1.
Exact model for mb is here: ASUS M4A88TD-V EVO/USB3 AM3
When I play audio files, the receiver can fake the signal into all 5 channels (I don't have a sub, so the .1 is not relevant here), so there's no issue of the receiver not accessing the available speakers.
The main issue is this: When I look into the Sound Control Panel, under Playback Devices, the active/default device is ATI HDMI Output. Also listed are Speakers (not plugged in), Realtek Digital Output and Realtek Digitial Output (Optical). I do not have any analog cables plugged in, nor do I have an S/PDIF (optical/coax) connected. The HDMI works, but only gives me the option of Stereo (2ch). When I go to the Configure screen for the ATI HDMI Output, I see a list of Audio Channels, but that list ONLY contains Stereo.
This is where I'm confused. I've looked through the other threads (and other forums) on this, but haven't found a good answer that addresses this problem. Some came close, but most folks were complaining about lack of 5.1 via S/PDIF, whereas I'm using HDMI. The most commonly suggested solution was to update to the latest version of the driver. I've done that. It did not solve the problem.
I was under the impression that HDMI would pass the entire digital signal on, so I'm confused why Windows thinks I only have 2 channels available, and won't allow me to select alternate configurations. This problem is independent of any individual video file, and I've verified that even with my highest quality videos, which DO contain 7.1ch audio data, the video (using either KMPLayer, VLC or WMP) will only play through my front 3 speakers, despite the presence of my back 2 surrounds.
I'm not sure what other configurations to check here. I know the MB is CAPABLE of outputting up to 7.1, but what gives with the failure of HDMI? Is this a known-issue with this particular motherboard? Is it an issue of using the HDMI out for everything? Or am I just too stupid to make it work (not that any of the options are mutually exclusive)?
Please let me know if there's any info I'm missing in here. All help and thoughts are appreciated. Thanks!