The Knob just spins yes, but what caused it to go was it kind of stuck, so I forced it, heard a crack and then it just now spins. It has always worked fine and felt nice and free before it threw a wobbler so perhaps its a stuck flap situation.
I think the best thing is to let someone have a look at it at the rally if I get up to it next sunday....Im sure Ive tried a different knob on it and it didnt make any difference. I'll double check though
I have the whole section spare, control right to the heater matrix spare out of a 1.6 xm 2.1 td estate, also many other parts that I will need to get rid off this year.