Missing events when syncing iPhone 5 running 7.0.6 to Macbook running os 10.6.8

I have ios 7.0.6 on my iphone 5. I've noticed recently since the update that the events on my iPhone Calendar does not all sync to iCal on my MacBook running os 10.6.8. Some syncs, but a lot don't (and not calendar-specific either). I tried rebooting and syncing again, manual back up, selecting one calendar and syncing one and a time, but none worked. How do I fix this, and is there a way to make my iPhone calendar over-write the calendar in iCal?