Well, after a few days of working good, the VU freezing came back, I think it's a case of removing the ribbons from the connectors, and giving the connectors a good clean, then snip off the ends of the ribbons before reconnecting to good wire.
BUT!... to save all of that, I have two spare desks, I chose the best of the two which looks like brand new, wired it up, set the OS code and it works perfectly, so it's like a Christmas present to myself but without forking out any money
All I have to do now is key in the plugin codes.