I was getting 1600 errors in iTunes while trying to jailbreak my ATV2 on a late 2006 iMac running OS X 10.6.8. Tried multiple times with multiple cables that I knew were good data cables because iTunes could use them to restore my ATV2 after it was bricked. Apple support forum pointed to USB issues, so I tried removing all other USB devices, still no success. Against all logic and reason, I used a powered USB hub between the ATV2 and the iMac and lo and behold, it finally worked. Just passing this along to others who may be having similar issues.
Thanks for the info. I’ll move this over to the jailbreaking section where hopefully others can benefit from the suggestion.