Peavey Special 112 problem in effects loop

[misterc57]

This amp only processes an input signal if I jump the effects jack with an instrument cable. I have heard of this problem on many amps.

In the past I have cleaned the jacks and the amp would work without the jumpers but after sitting around for a few weeks the problem starts again.

What can I do to correct this problem?

Thank you!

[52 Bill]

In the past I have cleaned the jacks and the amp would work without the jumpers but after sitting around for a few weeks the problem starts again.

How are you cleaning the jacks? Sometimes you will need to physically burnish the contacts clean and not just spray them out.

If all else fails, replace the return jack.

[misterc57]

maybe fixed...

I was spraying contact cleaner and inserting/removing a 1/4 plug repeatedly.

I did a close inspection of the inside of the jacks and there was this very tiny substance inside the return jack... I cannot tell if is paper or a spider web. I pulled that out and it is now working. Maybe this was blocking some contact.

But only time will tell if the problem is truely fixed.

Thanks, MC