I haven't had that happen to me, but once I did a sync, and turned the unit off, and ran to my car and dropped it in, and after a sync, it leaves you without a playlist, the display wouldn't come back, not matter what buttons I pressed,
and the unit just wouldnt start up, so a couple of "reboots" (pull, push, pull, push) it came back to me.

But an actual wonky (nice and technical description) display issue like that would get me pretty scared!

But to me, sounds like a voltage issue, like the display couldn't fire up to it "on" state, perhaps a residual charge left in the unit caused the screen to not clear? (Or am I simply rattling on about nothing?)