Check if the jack hits anything. Play it slowly and soft until the click appears or disappears. Check if the key leads (if any) are loose. Check center pins of the hammer, Whippen, jack for side play. Check damper, check damper spoon if they hit anything. There is much more you can check. Always start from the hammer down to the key. If you spend one hour to find this click it will pay of the next time you have to deal with a click and will take you only a minute. Cyrillus Aerts University of North Texas
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