The Method experienced and the one that has been investigative and proven to have a very impressive impact is the use of PC Triple C Wire as a Arm Wand Wire and if able to be achieved, exchange the Phon' Internal Signal Path Wire for PC Triple C.
PC Triple C is not found as a Metal in Connectors at present, Designs that use Pure Copper or a OCC for both Male Female are available.
Limiting the use of the OCC or Pure Copper Connector to the Cable Only is a method to create a partial result, that is able to be further benefitted by adding a partnering design to the chassis.
In the case of a RCA exchange a Pure Copper Low Mass / Low Eddy Connector will be a good selection.
XLR's from what I have been offered as a description, are a Low Mass/ow Eddy Design, choosing the metal for the connection is the additional consideration.
The impression made from the experience of being demo'd versions of the above has been so, that I am having the above done to the Pre-Amp that is to be Built for me.
When the HiFi System is back into action, I will be looking to have similar done to the other devices in use, the Power Amp's are already agreed to be converted to the above methodology by the Designer/Builder when the Design is to include the Balanced Circuit in conjunction with the Single Ended.