I was a professional ICE (In Car Entertainment) installer for over a decade…Bass Competitions, Custom Mounts, Motorized Amp displays, Lights,…ugh…the shame of it all…lol. Anyway, what I believe your issue may be is as follows. Modern audio equipment (and some back in the 00’s) have a “illumination wire” and is usually pink in color. You should have a wire diagram that came with the unit. If you do not… from memory the wires are as follows
Yellow = 12vdc constant
Red= 12vdc switched
Black = ground
blue = Power Antenna
Blue/white = Amp trip 12vdc Output to Amplifier to switch it on
Peach, Pink or Orange = ILLUMINATION
The most modern head units have even more options for cell phone, data line, voice in, voice return and other crap… So your make and model will reveal all the wires and colors to me so I can guide you with more accuracy. So that would help me immensley here.
I would…either unhook your Peach, Pink, Orange “illumination” wire from where ever you hooked it to and see if the problem goes away…or find out what wire in the car your “Illumination” wire is supposed to go to ( I personally never hook it up as it causes problems over time sometimes). Its purpose is to DIM your radio when the lights are on at night… most people never hook it up so the radio lights up but just does not dim.
You either have your illumination wire run to an incorrect wire in your car, have it hooked up in a loose manner making intermittent connection, or the unit is malfunctioning. Unhook the peach or pink illum wire…see whatcha get.
I hope someday I forget all the wire colors, wire gauges by sight, Amp bridge methods etc that I currently still reside in my head… I need to make room for new data in my Positronic Brain Module.
Sorry for writing you a novel…but wiring is a rather “specific business” imho… Hope this helps, let us know…