Windows Virtual Machine Platform and DisplayPort Audio

Question

The Windows Virtual Machine Platform interferes with the DisplayPort audio device on my X1 Carbon Gen 2 (old, but still good!).

The X1 Carbon Gen 2 uses the Intel HD Graphics 4400 chipset.

Audio was working perfectly fine over bluetooth, and built in speakers, but nothing from monitor connected to the DisplayPort plug. Windows correctly identifies the monitor's audio device (XG350R-C) but with the Virtual Machine Platform feature enabled, no sound comes from the monitor. Using the Windows Troubleshooting did not fix the issue.

Disabling the Virtual Machine Platform feature fixes the problem 100%, I get audio from the monitor over the DisplayPort device. However, I would like to run Docker/VirtualBox on occasion.

I found an old post about this issue here:
https://answers.microsoft.com/en-us/windows/forum/all/hdmi-no-sound-using-my-intel-hd-graphics-audio/3ecbd910-5011-4e4e-ae83-b73d4971221b

Answer 1

Docker and VBox shouldn't need this feature. Virtualbox will use the hardware virtualization directly.

Most likely the root cause is a driver issue that isn't playing well when it gets moved into the primary partition VM.