My PC broke and so I recently bought a new MacBook. I can't add music to my iPhone now, and so I click on "Manually Manage Music and Videos" but it says that it will erase my iPhone and sync to the new computer. My question is... what exactly gets erased? If it's just music and pictures and videos, that's fine. But is it going to reset me to factory settings? I have a jailbroken iPhone with settings just the way I like it and It'd be a pain to start from scratch... Thanks.