Headlights and dash lights keep flickering

[Cajun56]

I have a 05 1500hd silverado and recently my dash lights and headlights will flicker on and off constantly also door locks delay. I've just replaced the alternator and battery and it still happens. Checked my relays under the hood and I have a clocking noise coming from the parking lamp relay. I pulled it and the clicking still comes from the spot the relay was in. Anybody have an idea on what os going on?