After driving in stop and go driving for a period of time the transmission starts to act up. when coming to a complete stop the car will shift down into first gear after the stop and cause the car to leap forward. i have almost rear ended several cars as a result of this. it is a well know problem with the audi s-tronic transmissions found in the audi s5 cabriolet and the audi s4 models. the oil in the mechatronics unit heats up and causes problems with the circuitry which causes the issue. i have already had it in once for a "software update" to the tune of 800 dollars which did nothing. now it is looking like they will need to replace the component which can cost up to 11 thousand dollars if the transmission has been damaged.