HELP, WELDER PROBLEM

I have a miller 135, and it was working fine untill a few minutes ago, it started not being a consistent sizzle as im welding, it starts losing arc and popping constantly. i tried a new tip, adjusted tension knob, adjusted wire speed, straightened out the lead, grinded down for a perfect ground and NOTHING IS HELPING. Ill just start welding then it turns to shit. Someone please help.