I have had issues with mine locking up, and had email exchanges with the I Fly folks about it.  It had not done it in the air until a couple of days ago. Then I noticed the speed and distance were not chnaging as I flew in to the airport.  I had to shut the unit down and restart to wake it up.
I just saw the new software update, and was hoping that would fix it, then I saw this post.  Sounds like the new version 4.07 does not help?  I'll download it anyway, but maybe Walter can help me out with this?
Thanks,
Gary