The newer radio's are different
They have bluetooth and USB hardware inside the head unit.
Also they have HD Radio.
They have to be programmed with newer software.
I think this started around 2011 I'm not sure.
Also there are some radio's now that don't use the most bus.
I believe this may only be in Europe.
http://www.e90post.com/forums/showthread.php?t=687463