Uncaught TypeError: Cannot call method 'attr' of undefined

I try to use this module on fresh installation and appear this error of javascript:

Uncaught TypeError: Cannot call method 'attr' of undefined

Thsi error disapear if I change the line with this:
$(this).jPlayer('setFile', $(this).attr('rel'));

But the player don't work

I tested with Chrome Browser and Firefox

http://www.maxmendez.net/imageupload/images/pantalcec.png