My sat nav only works every now and then.. when i bought the car it didnt have the original audi nav disk in it (it had a burned disk copy), and over a year or so it started to only work every now and saying "unreadable disk".
I punted for a new 2012 copy on eBay, and that only works every now and then too.
I also bought and tried to run thru a CD/DVD cleaner disk, but its v.hard to play it through as you cannot control the nav disk player, so it doesnt seem to play the full cleaner disk all the way.
Any ideas what it might be??