Dear Jim, Thanks for your ingenious analysis of this problem. I think you have hit the nail on the head! Come to think of it, I remember that I never had the problem in the treble section and guess what, there are no dampers up there. Also damper springs are graded according to the section; light for the treble, medium for the middle and heavy for the bass, but the butt springs are all the same gauge. When I was at piano servicing college, my lecturers didn't believe me that there was a problem saying that no one plays that softly. Of course they were not pianists themselves neither are most of the techs in these parts. Next time I come across the problem I shall simply remove a damper to check/test the offending note/s without the spring tension. Amazing how such a simple mechanism can be so complicated. Thanks a ton for your interest.
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