I have a 99 740i w/nav and I get not only what u describe, but.....THE WORST STATIC NOISE ever heard this side of a sasquatch during mating season. My god, the first time it happened I thought someone was shooting at me. The absolute worst problem. There's no cure. I changed out the ignition switch per another BMW forum, still happened. I'm not about to drop the $$$$ fro a logic7.