Tap from behind?

Has anyone notice when your at a stop light and you take your foot off the brake to start to go, that you feel a little jolt as you start moving? I thought the guy behind me hit me the first time. I assume its just the way the rear brakes are releasing, but not sure. Anyone else?

Thanks.

One of my brake pads are somewhat hesitant to release from a stop at times. It does feel like someone tapped you from behind when you try to accelerate.

Nothing major...simple fix from the dealer.