There is no other way, but the menu doesn't have to be visible for the knobs to move through the menu. Anyway depending on the zoom level the knobs are not that easy to manipulate, so my suggestion is to map their functions to the keyboard. I have the outer knob assigned to the num keypad 8 and 9, the inner to 5 and 6. Then you can map menu, fpl, ent and dir to some nearby keys and manipulate flight plans and most of the MFD through keys. Much more convenient in my case because I am using realityXP with head movements, anticipation and so on.