Thanks again everyone.
Nick, the problem you describe sounds very familiar yet when I talked to Oakmere they were certain it wasn’t the wheels but I am beginning to wonder now.
I have recorded the sound it is making, it is not the best recording as it is just my iPad on the shelf behind the seat but does capture the sound if rather faintly. I have sent this to MMC to see what they think but if anyone knows how to post an audio file on TM it would be interesting to gather people’s thoughts on it. It is only 20s.
The wheel nuts are conveniently labelled ‘left’ and ‘right’ with the left one being the right handed thread so I turn it anti-clockwise to undo.
Roger