Whirring noise, and metal sharfs on pulleys

First post here,

So hoping all you veterans have some idea of this problem.

I purchased a 2001 model S40 1.8 (122bhp)

On my way home the other night,, I pulled up at a junction and heard a strange noise. It sounds like an electric motor in overdrive. And it gets louder with more revs, it is intermitent but can happen at any revs up to around 3.5k, not gone above that since I bought it.

The more worrying factor is the appearance of very fine metal sharfs/filings on the top pulley, and these can be seen all around the engine compartment close to the pulleys, and at the bottom on the plastic guard below the radiator.

We have figured out its not the power steering as on lock there is no altering in the sound, and the same with the heating/air con.

I took it into my local dealership (Rybrook in Liverpool) and the mechanic was dumbfounded as to what it could be. He also said that under the Volvo warranty they do not cover diagnostics, is this right.

It is booked in for its 66k mile service on Tuesday, and they have said if they can source the problem they will repair it if covered by warranty.

Does anyone have any clue what might be on its way out, or have they experienced this phenomenom.

Please give me some help and answers.

Steve