Stiff knob problem

Ive read the sticky knob problem thread, and while i have similar i also have a stiff knob. The vent selector knob is stiff and wont turn freely. Im going to start into sorting it and was wondering if anyone had pointers where to start looking and what to watch out for. Also have a thermo sticking problem but have read posts on here and preparing to get stuck into that. Going to put new expexpans bottle on at same time and flush/refill coolant (red)

Details. Hi.im Alex, in Northern ireland. Freelander 1 serengeti 03. Litteraly just purchaed and home 2 hours ago.

Detailed research on here meant I knew what to look for and landy generally very good in every other respect. 4x4 still in place and working, vcu not warming up after 50 mile drive. No whines or knocks. So, fingers crossed, couple minor items and she should be a tidy motor

Wish I had a stiff knob problem.

Try Viagra. Wont cure a stiff/sticking vent knob....

And to add, knob wont select some options. Just wondering what likely to be the problem.