Ed, the next time you are with the piano check a couple of things. First check how high the coils are from the plate. More than an eighth of an inch will cause what you describe. Solution here is to drive the pins down, with jack and three for so tunings. Second check the string deflection, especially at the end of the middle section. If the deflection is excessive there is little that can be done about it. If there is excessive friction between string underfelt and bearing points you can try some Prolube at these points and hope for an improvement. Newton
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