I have searched and read and have run into a brick wall. I'd love to jailbreak my ipod (version 2.2.1). I am trying to JB it on a PPC Mac (iBook G4). I have tried using the Untetherizer and I have tried using some other program (Full Sn0w I believe). My problem is with going into DFU. I have used a timer and have done the power and home buttons according to the times. The screen on the ipod goes black so I assumed it was in DFU. The problem is now iTunes will not recognize the ipod until I re-boot the computer. It's as if it is killing my USB ports. Does anyone have any suggestions?