Problem with Heater Dial

[Mr Leeches]

Just been out for a drive, and was changing the venting system to give air mostly out of the 'face' vents.

The dial was very stiff to move, and no wont move at all, the system that moves the valves inside to direct airflow seem to be stuck, there was a constant hising noice coming from the vents. this noice dissapears if i turn the switch to 'front window demist'.

now i can only turn the dial about half way.


any ideas?