PC says there are tracks, Rio says no

This is crazy. When I turn the device on, it says there is insufficient space to create a database, as if it's full. Yet when I try to play music, it says there are no tracks on the device! I connect it to the PC, go into Rio Music Manager, and it shows the tracks that I've synced to it. I've gone so far as to format it, but it still comes up saying I need to "delete content" because of the "insufficient storage". Shouldn't that have erased everything? grrrrrrrr