When driving the display will jump to the current route- show instruction display wiping out the map display. If you press either arrow on the display it will return to the map display but after a few seconds, it will return to the show instructions display. this will carry on for the rest of the journey making the nav useless. I have used the factory reset in the system menu a number of times and also gone online and done a restore on 4 occasions without solving the problem. Can anybody help?