No worries, it just makes it really hard for us to follow and keep track of what we already did answer and what not.
First check the grounding, that is the main thing for proper operation of a plasma cutter, then use shielded cable and attach the shielding to ONLY the electronics side or the control box, always do grounding from a single point namely from the main power cord and go from there to other parts of the machine, use a shield for each cable and attach all of them to that single point in the box. No daisy chaining.
