ROG Centurion HDMI Headphones not detected?

[rilner]

Running Windows 8.1 x64.

Plugged ASUS ROG Centurion headphones into my onboard HDMI. Phones light up red, but getting "hardware not detected" error during driver and firmware setups. What gives? Not seeing them in my device manager either.

 

[rilner]

To clarify:

ROG Centurion headphones have been plugged into my motherboard via HDMI (they have an HDMI connector).

Volume Mixer and Device Manager don't see them at all, despite them lighting up red being plugged in.

Drivers and Firmware from the ASUS website for these won't install, because I keep getting errors saying "Device not found". I think these are meant to come with a control dial of some sort, I just bought the headphones themselves New Open Box Style assuming they would work without any other gadgets.

I've also updated my Realtek sound driver. What am I missing?