Hi Jim,
Mea maxima culpa. Not only that I am an idiot. The swapping of the cathode leads would not/could not work because it is a PSE amplifier and the ECC82 is just used purely as a driver, so both cathodes have the same phase signal on them, whereas it is used as a phase splitter as in the 300b p-p.
Put it down to senile decay
At least swapping the primary leads has cured the problem - the secondaries would have done the same of course.
The difficulty with "clones" is that often the clone manufacturer does not have the original drawings to hand so can identify the readout wires as he wishes.
John