It's going into Audi Swindon next week for something else, so I'll mention this and see if I get any new info or a solution. Not keen on disabling the sensor, as it might make other lights harder to see, but I'll see what they think.
If OP has had it on for nearly a year and half with no probs, then I guess it's more of an annoyance than a problem.
Moved to the S3 from a Clio last August - before that, 9 years with no problems other than wear and tear - so much for the rock-solid Germany engineering! Takes me back to the days I owned a 5 Turbo - thought my days of shoddy electrics were over!