In some cases the "Learn MIDI CC" does not work. If you are working in Ableton Live you can work around this using the Live's MIDI map function.
- Click the small triangle / arrow on the right of the bypass button:
- If the Parameter you want to control is not visible click the "Configure" button and move the Parameter you desire on the UI.
- Now press CMD + M (Mac) or Ctrl + M (wWin) to activate the mapping feature:
At this point what you see should look like this:
- Now move the MIDI controller slider that you want to control the Parameter (in this example "Song Key") with.
Now you should be able to control the desired Parameter by MIDI CC messages of your controller.