Reading Norm's fine comprehensive list of squeak causes reminded me of a humorous incident: Our lead piano professor at our local college contacted me with a rush request to cure a squeak in the sustain pedal. I got to the offending instrument as quickly as I could, sat down and <squeak> only the noise seemed to be coming from my posterior. A further check revealed loose bench legs. A quick tighten and the squeak was gone -- apparently when she used the sustain pedal she pushed back against the bench; a clear case of 'for each action there is an equal and opposite reaction.'
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