I cannot connect to chassis directly. So, I need a work around.. if the ground wire is the cause, will reducing input resistance be ineffective? Will a fatter and shorter ground wire be helpful?
Discussion
Reducing input resistance won't fix a ground issue—it's about EMI pickup, not signal loading. A fatter, shorter ground wire will help by dropping resistance/inductance, minimizing noise. Workaround: Add a 10nF cap from ground to chassis for HF noise bypass, or use an isolation transformer on input. Test incrementally.
OK.. now we're getting somewhere. I already told you that a buffer pedal fixes this. Does that eliminate the ground Wire from the input as the cause?