There are many sources of such ringing, and Wilem is right in saying that there may be no solution, but I would trace the source before saying such. Dampers at bass end of middle section can be too short. Un stripped bass tails. Singing waste ends of treble strings. Open strings two octaves up. Poorly damped bass strings Poorly damped treble strings. Some damper levers resting on lift rod. Too fast timing of any damper. It can also be unmuted wires from pressure bar to tuning pins. Hard dampers. Any combination of above. Dampers should touch all strings, upper and lower parts of damper at the same time with equal pressure. That said there is an additional source which is poor assembly. They could be set too high or too low on the strings. The real problem though is that you just cannot get IN there. Trying to solve the problem my be an excersize in futility, but an educational one. You may isolate the problem(s) but it may not be worth fixing because of time required, but isolating the problem will provide it's solution. For hunting. Newton nhunt@jagat.com
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