Dead chipod

Hi.

A long time ago I've bought a very cheap mp4 player, I think it's a so called "chipod". I couldn't find any name on it or in the firmware. I formatted it often (forgot how) and now I can't get it working anymore.I can save files on it correctly when it's connected to the computer but no matter what formatting I choose (tried fat16, -32 and more), It says "empty disk" or it doesn't even start.

I'm using Ubuntu Linux. Please try to help fast because I need it working on Saturday.

Thanks, JoR