I have turned my Radio on once.
My Mac radio isn't even in the car anymore.
Did you put it in your Beemer?:lol
There's a long, old thread about this. Searching will help. The answer, in a nutshell, is no. Add the cable to the back of your Mac head unit and plug in anything you want using the Aux setting.
I'm not sure if this qualifies, but I burned a CD from songs I had in my Itunes. Various artists and songs all on one CD. The Mac stero deck played the entire CD without a problem.