This is a problem I (and others have) have since OS Sierra on Mac. El Capitan was fine. See also the tread on CB9:
The double click function does not work properly on CB (since version 9). I have this problem with my Apple Magic mouse 2 and my Wacom tablet. Others seem to have similar problems with other mouses. It is very annoying because it is hard to change a track name or open the editor.
For some reason double clicking works without problem with my Apple Trackpad (old one). But Apple Magic Mouse 2 or Wacom surface won’t work.
I also noticed that for instance to change a track name, double clicking in the mixer works way easier than in the project window…
Steinberg could you please check what is different in the coding there?
I am also curious to hear whether there are Mac users that have no problems with double clicking. If so can they tell what OS they use and what mouse?