Hello! I just wanted to add to the voices of the people who are having this issue. It started in 6.01 for me, and occurs primarily in instances where a lot of battle effect sounds are playing at once, particularly alliance raids, trials, and 8-man raids. Thankfully I'm one of the lucky people for whom turning DirectX 11 off made the issue stop, but I'd rather not have to do it as a permanent solution as this has introduced other annoying issues for me (slow loading times, crashes, occasionally models don't load in). I just tested it again today in the hopes that 6.05 might have implemented a fix, but it did not. If there's any information I can provide that would be helpful in identifying what's going on, please let me know!