itunes/ipod help

For some reason all of my songs play fine on my itunes, but on my ipod they dont play at all. It just skips through all of them. How can I fix this? I dont want to have to restart it and lose all my songs. I have like 400 of em. :cry:

oh and its a 2 gb nano. Dunno if that helps. And yes I have it fully updated.

Ok well I fixed it. Sorta.

I got all of my songs to play again on my ipod. Except for the 50 songs I purchased on itunes. God, itunes is such a crappy program. I deserve to get my friggin money back.