Ok heres my problem, i recently installed my D3, everything works, nav works, except i constantly have to "modify current location" not because the aarow is in the incorrect location, but because it is pointing in wrong direction. I can move the aarow in the correct location, and usually within a few miles it will start to be pointing off to the side a bit, and eventually will be pointing enough in the wrong direction that the unit doesnt recognize were i am. This may be an easy fix for some of you, but i dont know whats causing it, didnt know if theres a software update for the D3 or somethin