I have the exact same problem. I also have DSP and I think it has to do with the power to the DSP module. I can force the sound to cut out by turning on the rear defroster. I have the add-a-circuit in the fase panel http://www.partsexpress.com/pe/pshow...number=071-580 and that provides power to the convertor. I was thinking of trying this for power http://www.xoutpost.com/stereo-system...p-systems.html

I'll let you know...just waiting for it to get a little warmer outside to do the soldering.

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2011 550xi Carbon Black/Oyster, M-Sport, Premium Package, Technology Package, Electronic Damper Control, Dynamic Drive, Comfort Access, Active Seats, Surround Cameras

2013 X5 5.0 Space Grey/Black, M-Sport, Premium Package, Technology Package, Comfort Access, Surround Cameras