The problem I had was that the knob did not seem to be engaging with the controls.
The Kenwood label is thin aluminium and seems to be stuck on to the knob. Carefully remove with a thin blade. In the resulting recess is a plastic "shelf" which has protruding legs at each end. These latch on to the back of the knob. I prised this shelf out and forced the legs to come free but you could try to push the end tabs in from behind the knob if you can get in!
Once the "shelf" is removed then it's just a matter of slipping the spring circlip out of the groove on the spindle, lifting off the knob behind which is a spring.
My problem was caused by the spindle coming out of the casting. It seems to be a splined end. I tapped it back in. Should it come out again I will strip it down further and put loctite on the splines.
Stuart T
November 2019