This is the right area for this problem.

I have not had a NAV head in a Crossfire since I owned the original Red one, I sold it in 2010. I can't remember how you get the screen away from the "Bird Data" stuff - but you make it SOUND like the NAV receiver is only active when that data is shown AND that the NAV receiver in it is interfering with the Garmin's receiver. I still can't see how that can be, I wish I was in the area to take a look at it.