The amp in front of me , from a combo , so can resonate with the speaker,
not just i/p socket but most of the pot solderings have failed, 7 yearold
conventional solder. The large heatsink is bolted to the chassis but not
the pcb, only anchored via the pot + socket solderings. Board resonates and
breaks the solder. Either requires standoffs and holes drilled or simpler,
running hot melt glue on the pot side of the board over the pot pins and
board for mechanical holding.
I only ever replace pcb mount i/p 1/4 inch sockets with wired in chassis
mount ones , usually upside down and wires crossed over.

Most amps seem to be disigned well electroniucally but lack mechanical
and/or thermal/aerodynamic design, so often IMHO



--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://diverse.4mg.com/index.htm