Hello. Been using a virtualized Windows box with libvirt/kvm under Linux as my desktop for over a year. Hardware isn't anything special: A B150 board with an i3-6100 and 24GB of RAM paired with a (passed-through) RX-460 with 4GB of RAM.
This generally works great (thanks AMD!), but I've hit a roadblock recently.
My issue is with audio.
For audio, I'd been using (mostly successfully -- occasionally glitches) a USB sound adapter.
Lately, though, it has been useful to use HDMI for audio instead (because of other configuration changes in my life).
It doesn't work. I used to use HDMI audio and video occasionally for gaming in the living room (read: far away from the PC), and that worked OK.
Now I've got a situation where time has passed, and HDMI audio is both repeatedly and repeatably broken.
I've got a lengthy Youtube video of the failure here: https://www.youtube.com/edit?o=U&video_id=rvBsA7JtzC0 (you can fast-forward through most of it)
In the video I document firing up a new VM using the most recent easily-downloaded ISO (Fall Creator's Update) from Microsoft, let it do its thing, and HDMI audio seems to work one singular time before blowing up (and staying blown up) after all subsequent reboots. I then go through a number of easily-Googled and mundane troubleshooting steps to try to get it working again.
I can make this fail every time, all day, every day. I've already spun up a half-dozen fresh VMs just to make sure that I'm not doing something wrong myself.
How can I make it not fail?