Comment # 5 on bug 1163046 from Takashi Iwai

Also, how is the status of the given alsa-info.sh?  It shows that the second
HDMI port is connected and got the proper ELD.  So, from the audio perspective,
it looks already OK.

You can try to run "/usr/sbin/alsactl monitor" and plug/unplug the monitor.  If
this shows the event, and either "HDMI/DP,pcm=3 Jack" or "HDMI/DP,pcm=7 Jack"
shows true in alsa-info.sh output, the hotplug was done properly.
The rest would be either the remaining audio setup (that is specific to
AMD/ATI) or GPU driver problem.