After some more testing with various devices this morning, I am convinced the problem is with the Sync system in my C-max. I tried using 4 different external hard drives, all formatted as Fat32, and none worked, with one exception. I have a Toshiba 320GB drive that I put my entire music collection on, and when I first connected it, it did not work. After a second attempt, it worked and the Sync system indexed it, and all was golden. I then turned off the car, turned it back on, then reconnected the drive, and got the "Device is not supported" error like all the other times. I also see that people using this Sync system have been having lots of problems with it. I wish I would have read about this before I bought the car. I would not have purchased the car if I had known about these issues in advance. I have found no information online that is any help either, so I guess my only option is too bring it back to the dealer.