Unable to send audio to the desired display port, NVS 510


I’ve read http://http.download.nvidia.com/XFree86/gpu-hdmi-audio-document/gpu-hdmi-audio.html but I have a small issue with audio.

When connecting three displays to the card and launching Xorg I can see three separate screns on display 0: 0.0, 0.1 and 0.2. Video works perfectly on each screen. However I cannot pair the audio streems with the corresponding output in a consistent manner.

The easiest example I could give is the following.

  1. Launch Xserver with at least two displays connected
  2. Reproduce a video over display 0.1 trying every possible audio device

Note that display 0.0 is intentionally unused. The tested commands are (changing the card number, in my case is card1 because card0 is the onboard audio device):

mplayer -vo vdpau -display :0.1 -fs -ao alsa:device=hw=1.3 some_video.mp4
mplayer -vo vdpau -display :0.1 -fs -ao alsa:device=hw=1.7 some_video.mp4
mplayer -vo vdpau -display :0.1 -fs -ao alsa:device=hw=1.8 some_video.mp4
mplayer -vo vdpau -display :0.1 -fs -ao alsa:device=hw=1.9 some_video.mp4

And the end result is always the same: video is correctly displayed on the monitor connected to display 0.1 but audio goes to the tv/monitor connected to display 0.0. I tried driver versions 319 and 331 (packaged for Ubuntu 12.04.3).

I’m not really sure if this is a nvidia driver bug or if ALSA needs some manual configuration. In any case I would greatly appreciate comments, hints or pointers to documentation or code.

Many thanks in advance.
nvidia-bug-report.log.gz (111 KB)