I've been trying to sort out a libvirt/qemu Catalina VM using VFIO passthrough. I've got USB keyboard and mouse sorted, and my GT710 is working for graphics, however it isn't even recognised as an audio device (monitor plugged in via HDMI).
I've exhausted all of the libvirt possibilities and am starting to think its a macOS issue, I'm a bit new to macOS (well had a mac mini years ago but mainly for plex). Looking around the forums there seems to be a lot of HDMI audio problems - does macOS not support HDMI audio out-of-the-box?
I bought a GT710 specifically as it has built-in support including metal. There seems to be a myriad of kext fixes from AppleHDA, HDMIAudio, AppleALC, VoodooHDA but most seem to be deprecated, so its a bit confusing which one to use. I tried a few things in Clover (HPET, FixHDA, Inject Kext etc.) and installed WhateverGreen, Lilu and AppleALC but they didn't fix the issue and actually didn't seem to even load.
A lot of the posts here seem to be for people who have an audio device but no sound (DP to HDMI remapping?) but I don't even have a sound device. Interestingly I tried adding an ICH9 and ICH6 virtual soundcard and they weren't detected either - not sure if they're supported by macOS, but seems this virtual mac just hates audio! It was initially a Catalina beta 10 install, but its now GM 19A583
Any ideas? Here is my libvirt XML