Has anyone with a Nav III had it go from the map to the calibration screen, or to the Save Location screen all by itself. It doesn't seem to have anything to do with going over bumps or anything like that. It just does it at random times even while the bike is sitting still. Mine has been doing that for a while and Garmin tells me the only solution is to buy a new unit. Of course they don't make the Nav III any more so I would have to buy the IV.