When I plug my friend's ipod into the usb on my computer only my itune's library comes up. It asks me if I want to syc my friend's with mine & I don't because it will delete all of her songs. I just want to add some of mine to hers but I can't get her library to open on my computer. Even if my ipod is not plugged in at the same time. What software do I need to see her ipod shuffle library?