Grounding the exhaust system was a partial success in resolving the AM reception problem in that I now have reception where I had none. However, I still get a great deal of speed-dependent noise, screeching, centered around 1,300 to 1,600 RPM. (BMWNA rep states that we just can't expect Lexus-like reception. He is quite wrong. We can't even get Yugo-like reception.) Also, they are considering a shark-fin type antenna to improve things. Don't know if they are talking retrofit or not. All in all, this is a friggin' joke. There is pretty much no such thing as a contemporary car without decent AM reception. Except the X5. This, folks, is not rocket science, as they say. Acceptable AM reception is available for $19.95. My car stickered at $60,000+, and after a year and a half, all they can do is bring AM reception up to something as opposed to nothing. They tried, but it as all rather pathetic. Tom Purves, how can you accept this sort of thing?