Why does the car produce a rough gear change from 2nd gear down to 1st gear? on 2012 Mercedes-Benz S350 BLUETEC 4MATIC

Often, the car starts in 2nd gear and immediately decides to kick down to 1st gear. When this happens, the gear change is rough and noticeable. If the car starts in 2nd gear and moves up from there, there are no problems. Similarly, if the car starts in 1st gear and moves up to 2nd and so on, there are no problems. The rough, jerky change only occurs when the car attempts to start in 2nd gear, and then changes down to 1st gear.