If all four channels are out of phase they are in effect in phase relative to each other but may be reversed in polarity compared to any other channels. How many other channels are you using and how are they wired?[/quote]

I've swapped the four channels at the speaker(s) and now have correct sound and YPAO now confirms they're in phase.
I knew something was wrong, but I've never heard speakers that were wire wired incorrectly(not my own anyway.
Believe it or not, even out of phase they sounded better than the speakers they replaced.
Waiting for the sun...