I've just bought a second hand Audi Quattro A6 Avant. There is an intermittent but regular "peep" tone. It's not nearly as loud as the warning tone and is faint enough so that some people can't hear it but I find it quite annoying. I think it comes from the air-con system but would like to know for sure. Is it normal ? can I get rid of it ?, does anyone else have it ? what is it ?. Thanks so much.