iCal event duplicates on iPod Touch every time I tweak event

All of the calendar events I have in iCal that I change/update/tweak show up as duplicates in all their revised forms on the iPod. If I change the time of an event, it shows up at both times on the iPod; every time I add information to the event, every revision shows up on the iPod as a separate event... Even entire old calendars that were deleted show up on the iPod Touch. I have tried "replacing the selected information on this iPod with information on this computer" and it does not erase the duplicates. I even did a complete reset of the iPod, and it did not help. I think it is a problem in iCal. I am still looking for an answer on these discussion forums. Anyone out there who can help? I want the events I revise to permanently REPLACE the old information (no duh).

iPod Touch 4.2.1; no iCloud, no MobileMe, no WiFi Sync; I use a USB cable from my MacBook Pro 10.6.8 to my iPod Touch.

It sounds like people are having this same problem with iPhone and iPad, but no answers on discussion forums for those of us that do not use iCloud/MobileMe.