I've heard different schools thought when it comes to hub cone adjustment in general and nothing specific to SA hubs. The general advice is to aim for the sweet spot between eliminating play and avoiding binding, and it depends on the quality of manufacturing as to exactly where that lies. I've often been dissatisfied with the efficiency of SA hubs so I've intentionally adjusted for a tiny amount of play, but generally this results in the internals rattling once grease has migrated/settled, so now I dial out all play with as much care as possible to avoid over-tightening, which creates significant drag. It's a delicate procedure and one I'd prefer not to leave to a dissinterested or distracted shop mechanic.
Of course, your issue might be something else, but in my experience this is a common cause of SA noise. Another diagnostic test is to see if it increases when running higher tyre pressures.
It may also be the case that the factory grease lubrication was innadequate, but that's probably something to worry about further down the line.