On Dec 31 I picked up one of the last 2010 4s's in CA and everything has been fairly smooth until I plugged in a brand new USB drive into the center console USB port. The USB stick only had about 50 mp3 files on it and loaded up fine for the first few days. On day four I go to start the car and the PCM seems to be confused as on the bottom of the screen it shows permanently a "Loading medium..." message. This message locks up the entire audio functions (can't switch between sources, FM, AM, SAT, DISC, etc) and also bluetooth connection can be made but calls are worthless since it cant switch over the audio system (car is equipped with Burmester).

I turned off the car, unplugged the USB stick, restarted the car, and the same thing happens (have done this repeated times). It is like stuck in this "Loading medium..." mode. Has anyone run into this problem before? Is there a way to manually restart the PCM other than unhooking the battery?

Also, I just had the car serviced a two weeks ago where they upgraded the PCM to the latest firmware.

Any help would be much appreciated.