Thanks for your reply jbtsax,yes your first assumption is correct it is exactly that,the extremely thin buffer material I'm not sure exactly what it is made of can't see it too clearly but seems it may be some sort of fabric that softens the touch as the two come together,it showed itself in a noise and feeling you would put down perhaps to a rusty coil spring being compressed and rubbing against something causing a vibration in the mechanism,it took some time to isolate it to what was actually causing the problem I first thought it needed lubrication in the various pivots and rollers but nothing seemed to stop it and then I realised it was the back of the Bb key rubbing on the buffer pad as it rotated that set up the vibration,I was a bit concerned if adding a bit of grease to lubricate might not be the ideal thing to do taking into account the material of the buffer pad but you have allayed my worries thanks......John