Could be a problem with one or more wires finally breaking in the shifter assembly, which seems to have affected a large number of vehicles, including my 2007 328xi. Your presentation is a bit atypical, but it might be reflective of just one of the wires breaking. You can at least take a look at the cabling in the assembly, to see if this is your problem. Just make sure to remove the cable cover and peel back the tape, as the problems weren't evident in my case until I did that.
Here are relevant threads:
http://www.e90post.com/forums/showthread.php?t=842645
http://www.e90post.com/forums/showth...=447680&page=2
Hope it works out for you.