I thought it was one of the known rights of passage when owning an Audi of a certain age: The panic of thinking your DIS has succumbed to the inevitable dead pixel affliction, followed by the relief and slight embarrassment of being told by a more experienced owner that 'it's the button under the wiper stalk...'
C'mon, we've all been there once, and only once, some of us are just lucky enough to work it out before resorting to the forum. The unluckiest ones are those that take the 'failed' DIS to the stealers...
Joss, you've officially graduated to full A4 ownership, and can now kindly inform the next under-graduate to suffer humiliation at the hands of the legendary Button of False Doom...