hmmm.... I haven't been able to duplicate this. At least, not to the point that the unit needs a reboot, as the VR seems to boot regardless...
I let my truck warm up for about 10 minutes prior to leaving for work in the morning...
I've left the screen on Ipod screen, and after traveling about 5 miles, I realized that VR didn't work... I then hit Mode, and saw the nag screen and then remembered about this thread. But my phone paired up and VR came back within 2-3 minutes...
I've done this 3 times so far, with the same results. Although, now knowing about it, I purposely leave it in map mode when I shut the truck down for the night.
But even then, I reach in to crank/warm up my truck, I don't press OK till I'm ready to leave(10 min later), in which my phone connects shortly after getting in and pressing OK. I will definitely test some more as well...
I do however, have a question about not being able to use VR to respond to changing the source to my HD radio tuner(GEX-P20HD). Even if I get it to the point where it lists all my options... It still does not understand "Digital Radio"...