ipod nano 2nd gen won't turn on HELP!

Hi everyone, my sister bought a 2nd gen ipod nano. We charged it using iTunes. But when it was already fully charged and we tried to eject it, the ipod shut down and won't turn on. We tried reconnecting it to the PC and it turned on again. It works perfectly when connected to the PC via USB but is totally useless once disconnected. We have the latest version of itunes, updated the ipod's software, tried to restore and reboot a couple of times but the problem won't go away.

edit: sorry everyone, i posted this in the wrong section. any help would be greatly appreciated!