I took my volt on a road trip for the first time today, and more then once the navigation app just quit while open. Never seen this happen on any previous android phone where google maps, or any other program will just all of a sudden just quit and have the phone go back to the home screen. Sure made listen to music a pain too, since mid song it'll just stop, and if your going down the interstate at speed you really can't do anything about it (or atleast i'm not insane enough to).

is there any way to do a RAM test? You could have a memory problem.