Thanks so much, you are a fountain of knowledge!

I will have a look around for a replacement but much harder to source things like that here in the UK.

Will also look into modding a standard jack or using a jumper like you suggested, has to be worth a go.

Thanks again for taking th time to help me out...!!!

Have had another look and you are right, I thought that the jack socket contacts looked a bit different. I've just put in a normal mono jack socket so it will never work due to the switching issue.

So could you elaborate on the stereo switching trick....?

Thanks for your replies!

Thanks, any ideas would be great.

I have been asked to look at a friends Marshall JH-1 'Jackhammer' pedal after he 'dropped it'.

The foot-switch activates the 'active' red LED but as soon as a jack is inserted into the 'In' mono jack socket the light goes out and there is no signal throughput. With foot-switch in the 'off' position the signal bypass works fine.

I have now replaced the mono jack input socket (as it was very worn) and also the DPDT foot-switch but with no change.

Any suggestions greatfully received.