I have 2007 S550 with command systems isues. I took it the dealer because the nav stopped working and the message displayed that it was updating and was asking for dvd map software. This happened all by itself while i was cleaning the inside of the car with the radio on. The DVD/ CD and MP3 no longer works. The message says remove disk, but I can't because if wont come on. The next day I start the car and Nav is back up and running. However is running from older software version. Everthing in the command system works except the DVD/CD and MP3. The dealer tells me that I need a new command system. Over $2000.00 give me a break. Any suggestions would be greatful.