I have a 997 that came with the nav bundle, not sure of the nav bundle number, but it used to show very detail contour lines. Now the contour lines will show on the screen when I first turn it on for a while and then they disappear. They will pop up again and disappear for good. What gives? I did the last update 6.3 and now I switched back to the one before it (5.7?). Still no help.