Have an annoying problem with the HVAC system. Have a 2016 A6 Tecknik (Canadian spec) 3.0T with 89 km (~57K miles). Noticed last winter with fan speeds in excess of “5-6” and the temperature up (25C / ~75+F) and at highway speeds (90+ KPH / 50+ mph), a high pitched whistle or whine would start. It will come and go, and could be reduced or eliminated by reducing the fan speeds and is still a problem this winter. Not a good solution in very low temperatures. It is an annoyance I’d like to eliminate. Any suggestions?
Gerry in Edmonton, AB.