Not enough space for Music DB. Please free 200 mb

I can’t delete songs—or do anything else—because the only screen I get is the “please free 200 mb” message.  Can’t reformat because, under disk utilities, the device, or anything related to 7.8 GB/8.0 GB doesn’t show up.  Can’t change modes (I had set it to MSC before it froze up) because I can’t get to any other screen.