Whilst fitting a cheapy head unit I got today, I found a mystery lead tucked down the back of the head unit enclosure. I don't know what it's for


Doesn't look like part of the OEM wiring at all, so does anyone know what these leads are for? I dimly remember the CD changer control lead in my Audi looking similar, but it was nowhere near that big! Plus my lude has no cd changer

Ideas on a postcard then please

Josh