Sync and Hang w/E62

I have my E62 to sync with PC Suite every 30 minutes because I am constantly storing and exchanging information with Outlook.
Problem: It usually syncs fine throughout the evening, but sometimes it tries to sync and hangs right in the middle of the sync and freezes the phone I cant turn the phone off and no keys function, no backlighting but I can see that the phones says it still syncing. It does this for over an hour the only way i stop it is to remove the battery and reboot. Anyone having this problem and what are the solutions. :con?