I have never received a ding on autopilot. It is the only way I can drive on the freeway without getting unsafe following. I.e. merge onto freeway will give you a ding unless on autopilot, or people giving a large gap, which they never do. Also, while driving if people switch to your lanes without leaving a 2 second gap behind them you get a ding, unless on autopilot.
You sure you getting the ding on the freeway and not after or before? I used to get dings for hard braking all the time. I thought it was autopilot, it was actually me, right at my house
. I figured it out using an app on the store (iOS Safety Score Accelerometer). Turns out there is a curved down hill road that ends at a traffic light. I was braking to hard there, consistently.