Since I got my CC121 I found the AI knob too small and not suited for scrubbing an jogging. (slippery)
I searched on the internet and found the ALPS 863002 jog wheel and ordered it at Conrad Electronic (only € 2,49)
Or Völkner for even a lower price
Works great and fits perfectly upon the CC121 AI knob position.
Awesome! Always wanted to do something like this to use with just one finger like the jog wheel on the mackie MCU. Wonder if I can get this more locally in the US?
I’ve just bought “VA20 NITRILE Rubber V-Ring For Shafts 19-21mm” from a shop called Simply Bearings on E-bay UK, only cost £3.18 incl. postage, it stretches onto the controller knob and provides a lot more grip than the bare metal. I found that a number of retailers on the 'net do stock it also. I’ve no idea what it’s actually for, but it suits my purpose.