I just purchased a CAC-1080 DP1.4 to HDMI 2.0b adapter and I am unable to get it to recognize anything other than stereo 2.0 audio.
I am using Windows 10 Pro Ver 1803 build 17134.112 with an MSI GTX1080 video card. I am using Nvidia 398.36 drivers ( and tried older drivers as well) through a Yamaha RXA2070 receiver.
If I take the same cable and move it to the HDMI port on the video card, I get all the surround options in the Windows sound configuration screen, but when I swap it back to the CAC-1080, the only option is 2.0 stereo.
I have done a bit of detective work and it appears to have something to do with the EDID info. It seems to be stripping the receiver info out when attached to the adapter.
Do you have any suggestions?