I think if you pop over to the 8L forum you might get more help as this one is for 2003 onwards.
The connections to the DIS do fail resulting in missing pixels, especially on the earlier A3/S3s. The best bet is to replace the whole cluster, not the cheapest option though as you would need Audi to recode the immobilzer and correct the mileage for you too. Some people have managed to repair it but its not for the faint hearted or 100% fix. I'm sure there was a thread about it on the other A3 8L forum.