I have a 2008 escalade esv and when I insert the nav disc it says disc inserted is not a nav disc. The disc has the Cadillac label and is the disc that came with the vehicle. I called customer service and they told me to take it to the dealer. Problem is my closest dealer is over 100 miles away. He then suggested I could order a new disc but before I dump 200 on a non returnable disc I was wondering if there is a way to clean the head unit or another way to get it to work. The disc looks pristine, no scratches smudges etc. I appreciate any help or advice you all can offer and if I have posted this in the wrong place I beg forgiveness, I'm new here. Thanks again