I got something close to this to happen, *one* time. The one time it happened I popped up the HiJack menu by holding in the rotary selector. All other times I either held in the selector or held "OK" on the remote and it didn't happen. What happened was I got a blank screen for a second, then the unit rapidly began switching between aux, tuner and player. The remote wasn't active during this time. Perhaps significant was that I "recovered" the player by holding in the rotary selector, and the HiJack menu came back up, but sans the GPS item.

I tried to recreate, without success.

I definitely need to get in-car network so I have some way of figuring out what's going on.