My car is a 2007 (May 2007 build) with 232 miles on it. Today the NAV IDRIVE knob wouldn't respond (Spun freely when turned) and the display was stuck although it DID recognize IDRIVE pushes.

(Other IDRIVE sections like communication and climate were entirely NORMAL)

I tried to reset it by removing and replacing the DVD disk. That did nothing. So, I went on and locked my car. Wen I came back the problem was gone. Did the NAV reboot or should I do something else next time.
Any help would be appreciated.