Sound over DisplayPort (SST/MST)

Hi,

I’m trying to get sound on an Asus PQ321Q 4K monitor through DisplayPort (GPU is GTX Titan). I’ve completed the troubleshooting instructions listed on ftp://download.nvidia.com/XFree86/gpu-hdmi-audio-document/gpu-hdmi-audio.html.

With DisplayPort SST, speaker-test seems to work randomly about 25% of the time. That is, if I leave it running, every time it starts testing a channel, there is about a 25% chance that I’ll hear pink noise out of that channel, and 75% that I’ll hear silence.

Bug report log: http://dump.thecybershadow.net/3e9735da75722a01f05a5f021fc18bbf/nvidia-bug-report.log.gz

With DisplayPort MST, /proc/asound/card1/eld* all have “monitor_present 0” and “eld_valid 0”.

Bug report log: http://dump.thecybershadow.net/c620a86c0be8f1f9ce4996781caf39cb/nvidia-bug-report.log.gz

>>there is about a 25% chance that I’ll hear pink noise out of that channel, and 75% that I’ll hear silence.

Does this mean you only have this issue with SST mode and not with MST mode ? Did you also observe noise and silence playback while playing any audio, video, movie clip ?

Sorry for late reply, email notifications don’t seem to be working for me.

To clarify, I get different problems with SST and MST. With SST, most of the time I get no sound at all. I haven’t tested beyond speaker-test, but can perform more tests at your request. With MST, I get no sound at all, which I assume is because /proc/asound/card1/eld* all have “monitor_present 0” and “eld_valid 0”.

Hi, were you ever able to get audio from your monitor using DisplayPort? I was using SST and had audio, but I just switched over to MST and no longer have audio using the same monitor as you.

Audio over MST isn’t supported at the moment.