cannot charge up new SanSansa clip zip mp3. Pressed settings and nothing worked.

I got a the same mp3 player for Christmas. I don’t know why but since my computer did not charge it properly, I have a USB thingy that I plug the chargr into it. Then I judt have to plug it into the wall. Also, it does not  make sence but every time I look how much power it has left, it says either: 11%, 22%, 33%, 44%, 55%, 66%, 77%, 88%, 99%, or 100%. For some reason it never is 54% as an example. Does anyone know why and how to fix it?