Britney, Your problem is actually fairly common on newer pianos, I have even heard it on nice studio consoles and even a few grands. Apparently the hammer gets ahead of the jack and rebounds back against the un-let-off jack and hits the string a second time. This is common because it often happens so quickly that it is nearly unnoticeable and a high speed camera or sound track would be needed to pick it up; most players aren't bothered by it. Decreasing the hammer blow, then taking out the lost motion might advance the jack let off enough to resolve the issue, but I would only try it on a few test keys first before doing all this work. Increasing the let off might be your only hope if that doesn't work. Blaine Hebert RPT
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