Advice for people running clean, new systems + Retroarch sound issues:

I could not get xaudio to work no matter what I tried. I tried Windows 10, Windows 11, Windows 11 bleeding edge dev and none of them allowed me to have sound with xaudio (the rest, wasapi, dsound, gave me terrible performance).

The solution was to download the “DirectX End-User Runtimes (June 2010)”

I think it’s understandable that if you are reinstalling an operating system from scratch these runtimes are not included but it was driving me nuts since I had been upgrading systems I’ve had for a long time without issue.

A clean install of any modern windows os doesn’t contain this so you have to seek them out.