I just bought a pretty nice USED guitar from a friend of mine. It was working fine until last night, when at a gig, the signal started to cut out unless the volume knob was in a specific place. Does this mean I need to replace the volume pot? What else could this mean?

Thanks UG.
I play guitar in a ska band.
Modded MIM Strat > Fender Tuner > Bugera V55HD > Custom built 2x12