My 06 commander has had an error message reading the dvd-rom for some time now. It says to please check the disc. I have called the nav disc manufacturer and they said to pull the dvd out and put into the computer to see if it can be read. If it is read by the computer then the disc reader in the nav system is not working properly. The local dealers have never dealt with this type of error before so I wanted to ask you all. It's not that I need to use the nav system often now but the error message doesn't allow me to change the time on the unit. Anyone dealt with this type of error message before?