>>...bridge notching ...<< Can't imagine it being that. Search out separation of soundboard from ribs & cracks in soundboard, while someone else is playing the offending notes. Casters not touching floor, loose action nuts, top lid catches, fallboard mechanism (this is a vertical piano?) are excellent candidates. Any loose hardware screws: key blocks, keyslip, fallboard, music rest rack, hinges, etc. Touch parts of the piano while playing offending, anything to see if the sympathetic sound will alter its tune or even go away. Keith A. McGavern, RPT Oklahoma Chapter 731 Oklahoma Baptist University Shawnee, Oklahoma
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