try to put the disc in a different slot in the magazine, the system doesn't realize it can play MP3s until you play them for the 1st time, basically updates itself

__________________
2006 BMW X5 4.8is Lemans Blue/Beige/Dark Maple
-Nav, Comfort Seats, Heated Steering Wheel,
Rear Airbags, AUX Input
2009 BMW M3 Space Grey/Black/Carbon
-all options