iPod shuffle error message The iPod “XXXX’s iPod” cannot be updated because it contains files that are in use by another application.

I just took a iPod shuffle I recieved as a gift a few years ago out of the box and tried to load music on it for the first time and received this error message "The iPod “XXX’s iPod” cannot be updated because it contains files that are in use by another application." when I try to update the software or restore it. I've already rebooted my computer (Mac Air running Yosemite) and have nothing else running. How do I fix?