lost the sound to the announcers

[daz]

Ok, maybe I've gone mad, but played last night and everything was fine. Went into the crib and Steve-O challenged me but couldn't understand anything he said it was so muted. Ever since then when I play any game whether quick mode or franchise, I can barely hear the announcers. Berman is in audible, and the in game announcers are too. My presentation settings are on default and also switched to tv broadcast to no avail. I even cranked up the booth sound all the way and I can almost make out what they say. I have an xbox that I bought when the baseball season starts and all the other games I play run and sound fine.
Has anyone run into this or could I possibly have a bad disk?
I'm a little irritated. I was all set to play, but this kind of took the fun out. I didn't realize how much the announcers add in the actual games. Help!!!!!