alsa-lib 1.2.5 broke HDMI and DisplayPort audio
by sasha69 from LinuxQuestions.org on (#5JHJR)
HDMI and DisplayPort devices didn't even show in pavucontrol anymore after updating to alsa-lib 1.2.5 so I had to rollback to 1.2.4. I think it's an upstream bug: https://github.com/alsa-project/alsa-lib/issues/143