I had a radio / stereo problem that I found a simple solution for that I wanted to post for the next guy that has the same problem:

problem:
radio initially doesn't go off when you turn the key off, but then it goes off and won't come back on. The navigation works and the bluetooth works, but none of the buttons on the left side of the navigation work and the music part of the stereo (not the navigation voice and not the telephone function) doesn't work.

solution:
I pulled out the three fuses that power the navigation and stereo that are located in the back hatch fuse panel (not in the glove box). Then I put them back in and started up the car and the stereo is fixed.

I hope I help someone.

navin