So for me, I have the same thing happen. Sound effects are missing, and the ambient sounds just keep playing on a loop, even in loading screens. This isn’t a problem so much, as the FPS drops that come with it. When my sound cuts out, my fps drops from 60 to about 14 and if I try to exit the client, it hangs.
It’s only a problem because of the FPS drops that accompany it, because when you are in the middle of PvP and your frame rate takes a nose dive… Not fun… I’ve been having this issue for months, no idea why.