Does it help to say they only do it when the switch is on parking lights or head lights. never in the off position???? And when it does do it flicker .Its not that often.Disconnect the headlight switch, done so the lights will be on by default as soon as you run the engine. If they are fine then, it's the switch. If they act up without switch, it gets difficult.
nope stock headlights.Any chance the headlights were converted to LEDs?