Noise could be coming from any number of places. First things first, have you isolated that this particular guitar is the problem? Have you tried another guitar into your Marshall, and tried another cable?
Has it always done this, or did it just start?
I don't see anything obvious in the wiring from your photos, but that doesn't necessarily mean much.
Yep. The fact that it gets quieter when touch strings, bridge, or jack tends to indicate that the wiring is fine. This is what's supposed to happen. Shielding the control and pickup cavities is about all you can hope to do.
You'll never get it silent. You need to decide how much noise is too much.
Just looking at the picture, I would look closely at the point on the switch where the red and white wires come together, that joint looks somewhat suspect to me, and also definitely perform the Quiet the Beast mod, it works wonders. I would do that to all of your guitars, anywhere there are wires or components.
The wire from the bridge to "ground" is there to short out the closest source of EMI/RFI interference.*. So, yes, it's supposed to get quieter when you touch strings, bridge, or jack. Now if it's a whole lot more better touching the jack than with the strings, there might be a less than ideal connection there. Have you got a meter?
*. That's you Sparky!
Last Edit: Dec 31, 2010 18:46:20 GMT -5 by ashcatlt