"I have a problem with a new console piano. A few of the hammer return springs are clicking. 2 in particular are very bad. I tried weakening the spring on one and that made it worse. I tried pencil lead on the hammer butt on the other with no improvement." If the hammer return spring is a conventional style (spring rail) and if you are certain the click is coming from the spring, try spreading the coils of the spring apart very slightly with a sharp thin blade.
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