Weak Radio Signal When Headlights are On

[outatime]

When I switch on the headlights, suddenly the FM/AM loses a bit of signal. The car's batter is brand new. It also happened with the old battery.

What's causing this to happen? How do I fix it?

Thanks in anticipation.:wave:

[blk_shadow]

are you using grounding wires? or earthing kit?

if you are, maybe the wiring is not wired up properly.

[aaronng]

Is the wire for the antenna properly connected to your headunit?