I had the same prob. with my 530 with nav. every thing worked but the radio!? Went to BMW! All I got was a bunch of people scratching there heads!!! So I tried this first. Went to the back of my car and opened the right side compartment and inside was a bunch of fuses pulled each one 1 by1 until I heard my CD player recycle. Took that fuse out for 20-30 sec. set it bake in and vola radio worked! Had to do that a couple of times since then. But now every thing works fine! I hope this helps you and that it's a similar prob. P.S. Ignition. was off!!!