So in all of your tests, you may have been using a faulty (arguably DOA, if new) PSU. It's hard to draw any valid conclusions from this if n=1
In fact, n=2. I wrote I tried with two different PSUs for the same result.
As everyone tends to say this is a good PSU, I'm totally ready to take the blame on some error of mine, or of a bad coincidence of faulty units.
Eric