Started the car with the climate control still on, switched it off and a few moments later (around 1 minute) the noise stopped. Left the unit off and switched the car off and back on, no noise, switched the climate control back on and voila, a few moments later the noise is back
Sooooo... pretty good bet it is related to the climate control.
Does anyone know if changing the dash control unit will fix it or is there something else that needs to be done.
Cheers for the info Guvna1