kustom 200b2 pc 303 pre amp problem

[RAINPRO]

I have a Kustom 200b2 with a pc303 pre amp on one side and a smaller one on the other.
when I remove the pc303 from the chassis so it is un grounded it works great . when I mount it, it stops working as if it is shorted out.

I am absolutely sure that no wires, solder tabs or traces are touching the chassis. only the pot threads as it is supposed to.

Any one have any ideas.
Thank You Ron

[Enzo]

Not the sleeves of the input jacks?

[RAINPRO]

not understanding your question. the input jacks ground to the same metal chassis.

[RAINPRO]

What seems odd is on the smaller pre amp the input jacks have 2 wires black and blue and on the pc303 only 1 blue this appears to be factory

[Enzo]

You said only the pot shafts were grounding. I suggested that the input jacks also ground the circuit through their bushings.

[52 Bill]

When you mount the board into the chassis is it possible that there is some flexing causing a bad solder joint to open up?

If you leave the board out and working, what happens when you run a jumper from the chassis to each of the pot shafts. Is it possible that there is bridged trace on the board that is shorting the signal to one of the pot shaft somewhere?

Have you monitored the + and - 8 volt supplies on the board when you mount it?

[Enzo]

Or any chance a wire is on the wrong lug in the input jack?

[RAINPRO]

The input jacks are wired properly. I suspected that there might be a bad trace or loose solder. I reheated every soldered connection and dragged my iron along every trace all traces have a layer of solder.
I did not think of using a wire to each pot separately. I will try that now. Thanks

[RAINPRO]

Three pots cause short, but all three have a ground trace around them. The ground trace leads to the red wires which go to the amp board. That doesn't seem right. shouldn't the ground trace go to green?

[RAINPRO]

sorry my bad . trace does not go to red. lost tract of it along the way.