Mine did this exact thing the other day at the dealer. They checked it out and said that it needed to be replaced. I found this on the forum.

Disconnect the DVD from it's power source. I took out the four screws to get to the power souce. There is a tool that the dealer had.

Reconnect the power source to the DVD player and quickly hit the eject button. This will eject the disk.

Once it came out, I was able to put in the new disk and it ejected it just fine after that.

Here is the link that I used...
http://www.xoutpost.com/navigation-sy...eject+nav+disk

Ron Aguilar