Check fit of Pinblock to Plate Flange. I have seen quite a few that have not been fitted & they are never stable unless that is corrected, & it can be. Once a new piano has settled in (at least gone through wet & dry cycles) if the structure is solid & serviced regular, it will stay in tune. Properly installing a Climate Control System really does help. Yours truly, Willis P. Snyder, RPT
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