Ive been listening to mp3 while playing WoW since the first week i began playing, because im not to fond of listening to the WoW own BGM. When i found out about this a month back when i troll WoW EU forums there are no different on my WoW performance ( note that my machine is abit old ) so turn off my music player and my WoW performance drop down to death, i even lag out due to fps restrain in shattrah... this little wonder that ive been using for around 2 years and never found out... i lol'd a little inside.

BTW most music player works, im using jetaudio and ive tested it even with iTunes, but not winamp thou coz i hate winamp lol.