[chicken]

Can you get the battery out of the player at all or is it sealed?

It's just you can fix some batteries by freezing them, but you don't want to damage the rest of the unit. This is really a mobile-phone trick but I don't see why it wouldn't work on an MP3 player if it has a removable Li-ion battery too.

If this does help at all then please follow these instructions: Wrap battery in kitchen-roll, place in a sealed food-bag to keep as dry as possible. Put in freezer overnight. In the morning unrwap the plastic and place the battery still in the kitchen-roll somewhere warm, but not too hot and leave it a good few hours to thaw out.

This is of course risky, but it's worked for me and if your battery is about to die anyway, who cares?