We bought a 2005 Audi-A6 2.0 quarto new and it has always shifted hard immediately after backing out of the garage and then forward from first to second gear. The car shifts very hard into second gear only once. It actually lunges forward noticeably. After this event, it doesn't happen again and shifts normally (all gears) for the rest of the day. Once it happen twice after a stop. We have always purchased Audi service, they have updated software and presumably checked oil and etc. The service personnel can not duplicate this problem and no other maintenance was ever needed. Otherwise the car works perfectly. Please suggest!