Its not often used for long journeys, but recently, when it is, our e-tron had started to exhibit stuttering / jerky gear changes at low speed. Not always, but often enough to be an issue. There was also the occasional error message - 'gearbox fault' or 'drivetrain fault'. So it was booked in to Brighton Audi to be looked at. Turns out that it's a faulty mechatronics (sp?) unit, and replacement is needed. Vehicle specific and coded to the car in Germany apparently. So at the moment there's a new shape A4 on the drive as the part will take several days and the dealer didn't want me to have the car back in case it failed completely!