Hi everyone i just picked up a Miller Suitcase 12vs and i am having problems with the wire feed speed it will go from 100 to 780 inches per minute in about an 1/8th of an inch of rotation in the knob i have taken it to a Miller rep. and they have told me the PC1 board needed to be replaced so i replaced it and still the same then i replaced the meter board also and still the same thing i have also replaced the "pot" and still nothing. i am at a loss please if anyone has info i am up for any ideas.