This happens to me all the time. It actually jolts my car forward when idling and it kicks on and off over and over and I sometimes shut the AC off just so I don't have to listen to it and feel it vibrating and jolting the car. So I can tell you this happens to someone else too. I assumed it was normal for the vehicle. My other vehicles cycle too (obviously that's what ac compressor do) but they don't shake the car.