I started to post the same thing you just posted but then I thought about your report on your luxman that you found circuits hooked to the ground rather than the black wire....
Sorry @carlsbad2 but I absolutely did NOT mean to say that. I meant to say neutral and hot were reversed.
Neutral is not ground.
In the US with 1 active wire (hot or line) and another that is normally 0V (neutral but not ground) we prefer to fuse the hot wire when only one fuse is present in the circuit. This means that high voltages are present in the shortest possible path when the fuse has blown. The alternative, fusing neutral, leaves a long from the line through the circuit until it is broken by the fuse. A bad thing.
In fact, oddly, the Luxman also has no ground pin in the inlet,, so impossible to reverse ground with any other conductor from the wall.