For a couple of months now, my NAVI has been constantly rebooting with the occasional “consult your dealer” message. I understand that the NAVI DVD drive reader likely requires replacing. The other day, however, the NAVI screen started acting up... see attached photo. Is this also a symptom of the bad dvd drive, or is this the screen itself which has also gone bad? For the time being, I have unplugged the DVD drive completely which renders the screen dead. Any help would be greatly appreciated.