DDK - Die Deutschen Klassiker

A while back I noticed my brake lights had stopped working. I then replaced the switch making sure to adjust the range of motion on the little lever to match up with the brake pedal travel which temporarily fixed the problem. I adjusted the range of motion on the switch again slightly which worked for a bit but then the brake lights stopped working again. I then replaced it with another switch thinking maybe this new one was also faulty but am having the exact same issue and seem to be going round in circles. Does anyone have any suggestions?
Thanks
Sam

Possibly a bad earth.

Is this the switch behind the pedal board or is it wired up to the master cylinder?

Ok thx, will look to that. Yes is the switch behind the pedal board.

Not familiar with the exact arrangement here, but on setups where a brake light switch makes contact once the pedal had moved away from the switch it is very important that the switch position is adjusted so that the on-off point in its travel is just after the pedal leaves it's mechanical stop. Ie: if the switch becomes the thing the brake pedal rests against when that brakes are not in use, the switch wont last long.....W

I took it off and the contact seemed to be slightly corroded despite it not being on the car for long. The contact area is so small though that I can't imagine its hard to lose conductivity. I filed it and put some conductive grease on so hopefully that should last.