I have the same problem, BMW are now buying my car back and ordering a new one:
http://f10.5post.com/forums/showthread.php?t=751143
L16GSY:
My dealer also replaced hydro bearings on my car, re-balanced wheels and tyres several times and eventually replaced my Pirellis to Goodyear Excellence but nothing has solved the problem. Please update after you have driven the new car for a while, thanks!