Just adding my experience as well. Prior to end walker, no issues; with 6.0 patch, had issues, but they were not too often and could be mostly ignored; now with 6.01... the game is unplayable... The audio is cracking up and popping everywhere, and the cut scene audio doesn't even play correctly...
Example video of cut scene audio not working: https://www.youtube.com/watch?v=srqnzEGdOAE
I tried lowering the default sound quality, different audio device and processor, restarting the game client, reducing graphics settings, and reverting back to directx 9 client. Only the directx 9 client revert worked.