iPod iPod Shuffle not being recognized

Hi I have 2 first generation 1 GB iPod shuffles, one of them gets recognized by my MacBook Pro, the other doesn't get recognized. I don't know what's wrong with it. Any advice?

I also want to add the lights don't light up at all if you plug it in, but if you turn it on without connecting to the computer the lights work as normal. I tried connecting the shuffle to the computer while it was on and that didn't work.