creda simplicity 1200 washing machine faulty spin?

My Creda washing machine works ok but recently it has started to become very noisy on fast spin and seems ready to "take off".
It completes the whole cycle ok. I have checked the mountings and belt tension and all seems well. I suspect the motor brushes may be at fault ( the machine is about 10 years old and the brushes were replaced by a professional installer some 4 5 years ago and its been fine since then. This was expensive and I would like to know if there an easy way to check this out before caling someone out.