Streets that were going up and down straight on the screen are now skewed to either side by about 30 degrees. Anyone know if there is a way of recalibrating the nav system?

 

I don't have the NAV, but I've seen posts that say it's tied into your in-car compass. Have oyu tried recalibrating your compass? See the manual for the number code for your part of the U.S.

One other thought is that maybe you've accidentally changed the preferences that make north be straight up on your display.

Mike

 

please see navigation manual starting 11-18 "How do I adjust the display?"