That little chip of chrome missing is what is causing the leak. That universal yoke retainer is no longer any good. What you can try is to file of the chrome with a flat fine file. The brass underneath is very soft. File it flat. If it doesn’t work then you’ll have to replace that part anyways. Try it cause its not going to hurt that part anymore. Just take enough chrome of so that its flat across. That part should retail for about $16. If you want to change out to DIN its about $60 parts. If you do this yourself don’t tourqe more then 30NM on a brass housing. You can double thread the 1st stage very easy also. So be very careful. Thanks for keeping us all informed.