I downloaded Senuti and hooked up my ipod to my Mac (I'm a switcher), but it asks me whether I want itunes to delete what's on my ipod or replace it with what music the itunes on my mac has. How do I "de-sync" my ipod from my PC and sync it with my Mac? I'm confused. What exactly do I have to do in order to make it work? Btw, this is the same message you get when you hook up your ipod to someone else's computer.