YES! I FINALLY found the fix in the net after HOURS of search. Now I can normally exit the game and go to the settings menu WITHOUT to kill the process...
Here is the solution written:https://forums.x-plane.org/forums/topic/325851-xp-1213-4-on-linux-freeze-not-ctd-on-exit/#comment-2864294 and here https://forums.x-plane.org/forums/topic/326955-x-plane-12-hangs-on-exit-linux/
I only needed to run sudo ln -s /bin/true /usr/bin/pulseaudio
I am still learning linux but I think its an symbol link creation... Linux wizardry that I want to learn and thats an very good thread to start learning some things hehe
Thanky to you all for trying to help me.
Have an nice flight :-)
EDIT: So naturally I can now access the CL650 settings :-)