Brake lights go out, then come back on

I bought a used '02 Frontier with the brake light issue. I started the fix by
gluing a penny some one else's attempt at fixing it with a plastic body panel
fastener. The light would go out, but some time later would come back on.

I then took out the fastener and put in a small bolt and nut. Same thing. The
light went out but an hour or so later would come back on. I then glued a
penny to the head of the bolt. Same thing again.

I can manually push the button and the switch seems to work properly. Any
ideas on why the light would go out initially, but then come back on without
the truck moving or the brake pedal being pushed at all? Should I replace the
switch? Replace the bolt with the proper rubber stopper?