After years of being sat in a cupboard, I revived my epiphone les paul Custom but only to find that the neck pickup had lost almost all volume on clean and was significantly quieter than the bridge on distortion. After checking resistances on both pickups and all pots, nothing seemed odd. Following an intensive google I cleaned up the selector switch which solved the issue briefly. I decided to replace the switch and after soldering it all back in, the problem is literally reversed. Volume on the bridge is minimal while the neck is now full bodied and beautiful again.
A further plot twist came when I reversed the wires on the selector to find the bridge bellowing once more when Rhythm is selected. Obviously both pickups and all pots work, brand new switch but I am completely baffled and need your expert advice!