Every time I connect my iPhone to MacBook Pro to sync and charge, it's not possible to make or receive calls. Even after unplugging, I can't make/receive calls and I have to either turn it off or soft reset. Is this normal? I have an iPhone 3G dock. I have tried several ways to connect it: direct to MacBook Pro, to Apple Cinema Display-MBP, to Belkin USB Hub-ACD-MBP. I have even tried without the dock. Same problem every time. Any idea?