Hi Eliot, The action may be moving too far and some keys my be rubbing adjacent damper levers. The hammers need to be spaced so that there is 1/2 the amount of hammer on the left side of the unison as there is on the right side, except in the bass where the opposite is true. The action should shift only enough for the left string to be missed by the hammers. Also check the pitman to see if it rubs the key frame. Newton nhunt@jagat.com
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