Replying to IPOD

Alright, so my ipod is only 8 months old, black latest gen 30gb. Its still got 15gb left to spare on it, but everytime i use it, the battery lasts for about 4hours and then its dead. Another situation i have is that with some artists it will completely freeze up, and will just stay on until it dies a few hours later. I have no idea what the problem is, but i do have a warranty on it. Is there anyway to fix the problem w/o sending it back aka losing all my music? (my laptop crashed and i lost all my music and data as well so thats a lot of shit to try to get back)