If you can pluck the strings with a guitar pick and get more tone than from the
hammers it is then a hammer problem.
If the tone and voluum are about the same then it is a board / bridge problem.
Check bearing, crown, plate screws and bolts, and look for anything abnormal
like crud on the strings, felt strips in the wrong place, etc.
If all this is "normal" and the customer is complaining then get someone more
experienced to help with the diagnosis.
Newton
nhunt@rci.rutgers.edu
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