That's what it usually is. See if there's a loose screw. If there is, tighten it. If you tighten it too much and the peg won't turn, loosen it just a bit. Usually it's the screw that goes through the button. But I don't know what kind of tuners you have on the banjo.
Austin said:
You think it's just the outside screws?
Jody Stecher said:
Look for a slot in which to place the blade of a screwdriver. Inset blade in slot. Turn clockwise.