QubesOS
No sound over hdmi when using hdmi over usb c
Qubes OS release
4.2
Brief summary
When I'm using HDMI connector everything work as it should, when I try to use HDMI from my usb c dock/hub there is no sound even if I chose the right output and I can see that there should be sound on that output in volum control app.
Steps to reproduce
Connect usb c dock to usb c, connect hdmi to the dock, choose output, play some music.
Expected behavior
There should be sound over HDMI
Actual behavior
There is no sound. Also, when using an extension cable with the dock, displays randomly turn black. This does not happen on other computer with debian.
Additional information
I will add hw specification later, but it looks like os specific issue is not a hw related issue.
Have you tested whether this issue also arises with e.g. a live linux distro?
I have the same issue with a set of Lenovo Legion Go glasses (basically an HDMI over USB-C screen and speakers). The display works fine out of the box and the sound device is recognized in the mixer, but no sound comes out. As suggested, I tested them with a few live distros (Fedora 37, 39 and 42 and Ubuntu 24.04) and they all had the same problem.
I also run Qubes 4.2 with sound in dom0, but it does not seem that it matters here. Any idea where to report the issue?
