It's another problem, the tyres have developed lips on the tread (apparently) I can't see what the guy was on about but he suggested trying my winter tyres and it took the noise away. I was convinced it was a wheel bearing, and a German garage told me so but it passed the mot and I raised the question of the wheel bearing in the test centre, they rechecked and said they were perfect. I then described the noise which is where I got this answer from, having read the thread on JDM tyre feathering I took it to be something like that although I'm not sure???
I'm ordering some new rear tyres on Monday going for falkon to match my fronts, after the test I did with my winter tyres I'm certain this will remove the noise