I have a 2003 X5 3.0 with Navigation, Standard Audio System with an Auxillary Port to connect an MP3 Player. Today all of sudden all audio sources(FM,AM,Tape,CD,Aux) only work if my lights are turned to the first or second position!! If I turn the lights off no more sound. I can 't even hit the mode button on the Navigation and cycle through the sources when lights are off.

I would think some ground wire or some weird wiring issue is happening. Any thoughts on fixing it myself without bringing it into the dealer or a mechanic?
TIA,
Dennis