Audio drivers have long been measured using IAudioClient::Initialize success rate:
https://docs.microsoft.com/en-us/windows-hardware/drivers/dashboard/audio-measures
Some systems have more than one audio driver on them; for example, you could have a Bluetooth audio device, an HDMI or DisplayPort audio device, and built-in speakers all on the same system, all running different drivers.
The Windows audio team has created a new version of the IAudioClient::Initialize measure https://docs.microsoft.com/en-us/windows-hardware/drivers/dashboard/pct-machines-with-subpar-stream-... which limits itself to audio streams on the driver being flighted. It is currently being evaluated and will be used to make accept/reject decisions starting October 15th 2019.
If your audio driver fails this measure, please work with your audio IHV to get a fix for the IAudioClient::Initialize failure in question.
