Make sure the knob is gripping the top of the potentiometer (volume control) post. Pull it off and either open up the split shaft with a screwdriver or put a bit of tapeon post to grip.Push back on -if it still doesn't twist the pot is seized and you will need to replace - try a squirt of WD40 in it before you go to your Guitar shop. It may loosen the control.
steve
April 2009
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