We have a floodlight on our back porch and I just noticed tonight that it has a chirp (intermittent) that I've never noticed before. It stops if I put pressure on the cover or push on the switch but as soon as I let go it starts again. It also chirps when the switch is in the off position. Not a crackling or poppiing noise, definitely a chirp, like crickets.

Could be just metal rubbing against metal, such as the mounting screws or strap.

May be worth having it checked out, and replaced, just to be sure there is no problem.