Was at a gig with the guitar sitting on its stand and someone has walked past and knocked it over and the volume knob has collapsed into the guitar.
A picture would help, because I have too many questions to imagine the damage.... is it an acoustic or semi-hollow body? Where is the knob mounted? etc.
But yeah, from your brief description it's probably repairable. The question is really whether it's cheaper to repair than replace.
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Post a pictures and we might be able to help a little more. Typically, I would say this is repairable, but it might not look that pretty depending on what type of guitar you have. Post a pic and I will have a little better idea of what you are working with.
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