I have tried using different udp ports but that still hasn't worked, tried running everything as administrator - that didn't work; tried running individual programs (WSJT-X/Log4OM/Omnirig) as administrator - that didn't work. And before you ask, yes that was with a reboot between each setting "just in case".
In Log4OM, if I click Help -> Realtime Log and (just for fun) enter G4POP into the DX Call field of WSJT-X this is what appears in said log :
It appears that data is coming through - just its wrong.
Oh and I have also uninstalled WSJT-X and reinstalled it (vers 2.1.2) and just for the fun of it vers 2.1.0 and both seem to be passing the same data ie I get similar messages in the realtime log.
And for a compete bit of fun, I installed WSJT-X (v2.1.2) and Log4OM on my laptop. Quite surprisingly it shows the same symptoms as the main computer.
Its really nice that it works for most people - just has me puzzled why it won't work on mine.
I have logged a support request so will await some feedback from that
Thank you for yor time.