I am pretty certain it is the problem. The noise used to stop if I pressed the air circulation button. After someone attempted to repair it, the noise is constant and the main heater fan broke just to add to the list of things to do. So now I need to get it fixed.
Does anyone know if there is an alternative to replacing the air circ flap motor ? Can it be disconnected and what would the effect of that be? Could I lose the windscreen blower as a result? ;)