One works good, the other one doesn't.

Question

My two granddaughters got idenical (Delstar DS 31024) MP3 Players for christmas. One of them works the way it should. The other one doesn't even hook up the same way. I had to create a folder to record from. After getting the music down loaded to the player, it won't play back. When the play/pause key is pressed, the player says goodbye and shuts off.