Throw away the standard infusion setup and replace with a large SS ring and large twist shackle.
I am on my 3rd Infusion and still dont use the nacra supplied setup. Their rings are to small in thickness and stretch and the knot gets in the way.

I use the same setup the old Nacra 5.8 had. It is a 50mm SS ring 8mm and large twist shackle. Never have a problem.