I've had my E39 in the shop twice now to have them diagnose my radio problem, and still they can't figure it out. I have an '01 530i w/Nav and the upgraded system, don't know what you call it, I think DSP? Anyways my unit turns on but no sound. Nav works, but she doen't talk to me. They thought it was the amp so they replaced the amp. NOPE!! so they thought it was the head unit. Pulled it out and checked it over. NOPE!! Then the tested the fuses, its all good. Its back in the shop today and still no answers. They said it might be something with the headunit. But the part they ordered was $700 and it goes in the trunk. WTF!! Anyone have this problem??

sounds like your shop isnt a bmw dealership. i hope you didnt have to pay for that DSP. since it didnt solve it.

651201 APR 02 Campaign - Alpine CD53 Radio Reprogramming
651201 JAN 02 Campaign - Alpine CD 53 Radio Programming
840600 AUG 00 Campaign - Navigation System Failure

Its a private car luxury car dealership with a service shop in the back, with BMW certified mechanics. "So they say" :shifty