I get the same noise think. I get a noise like a low pitched version of somebody pulling a chair across a shiny floor. Only for a second when at biting point, sometimes quite loud though, happens maybe once a week. A few years ago I was told I need a new clutch by Honda (due to high biting point) which would cost £700 so I am still saving but gradually over the past few years the noise has got gradually more frequent so I am pretty sure it something in the clutch but I can't be any more detailed than that. Another thing to mention is that mine is an after market clutch.