sansa clip+ does not play songs

Hello again everyone IM back once more. Yesterday I had  a problem with my clip when it was freezing constantly. I restored to factory settings and formatted it. Later I downloaded the software update for it and loaded 500 songs on it. Today I go to play and only get through about 3 songs before it stops playing them. PLEASE NOTE: it does not freeze anymore and I still have full control over everything. It just wont play songs. I can pause, format, change settings and everything else. The only time it seems like it wants to lag is when I try to skip to the next song. Still, it does not want to play.