It sounds like you have a sync multiplier. (You are syncing from two or more different locations and one is automatic) I would suggest turning off iTunes' ability to sync contacts and calendars since you use Google for that, and turning that off should result in the auto-sync shutting off as well. Let me know how it goes! In iTunes, uncheck "address book" and "calendar" sync, and restart the computer. If that fails to work, its time to make sure it is not a virus or system registry error. To clear virus issues www.malwarebytes.org and download the free scanner, update and scan. Restart the computer when prompted. Then clear registry and temporary file issues, www.piriform.com/ccleaner , run the temporary file cleaner and the registry cleaner in the registry tab. Restart the computer.