Just got myself a 1999 E36 318IS Coupe, only 16500 on the clock from the dealer, really nice car, it's avus blue, it's fast..

Except, I get an annoying high pitch noise that I hear when driving on uneven surfaces, speed bumps, minor dips in the road, I am getting the car checked out by a dealer as I have the extended warranty and only had the car 6 days. 

Is this a characteristic or common concern with the model??

Oh yeah and the stereo is not the best either, it has the changer but the sound distorts very easily and I wonder is it just a matter of replacing the rear speakers or if a more radical approach is needed.

Even with these minor problems the handling and feel of the car is still really good and it's an enjoyable car to drive.