If it's still under warrenty I suggest calling Apple and have them replace it. If it isn't there are plenty of websites out their about battery replacement for ipods. If those fail, Iriver and JetAudio make awesome players that I highly reccomend
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-- edit --
Try flashing the firmware on it too. Flashing the firmware can solve alot of problems. Just be sure you know what you are doing before you attempt to flash it. Good luck
