You could try letting down the tension and playing the note hard. This would loosen the crud between the windings. Or take the string off the hitch pin and coil it around itself, which will do the same thing. When you remove the string, note if there is any twist in the string as you take it off the hitch pin. Twist the string in the direction of the winding to tighten the coil before you replace the end on the pin, about 1/2 turn in the single strings, up to a whole turn in the double string area. If they are already very tightly twisted you may have to release some of the twist, as that can also inhibit free movement of the strings. Paul McCloud
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