Ok so I want to jailbreak my 2nd generation iPod Touch running firmware 3.1.3 for the first time I've never jailbroken before. I am using a mac and do not have access to a pc, and my iPod model number starts with mb. I ran PwnageTool and got the custom .ipsw file and put my ipod into recovery mode like i was prompted. Opened iTunes and option clicked restore and selected the custom .ipsw file but then iTunes says preparing iPod for restore for a long time. Then gives me error 1604 I've tried changing usb ports and accounts and I rebooted my computer rebooted iPod restarted iTunes and tried multiple times, and nothing works what am i doing wrong? Thanks for your help.