My macbook suddenly started making these deep echoey sounds when I watch Movies, Play Itunes, and Mac games. This recently just started only a game doing it but by the end of the day a DVD was doing the same thing. The applications work, but the sound is muffled and very deep, almost impossible to make out the lyrics. I have tried to mess with the sound in my prefrences but that has no effect, If anyone can help me resolve this issue it would be highly appriciated!! Thanks.