I noticed that there's a light strip the door speakers, yet only the 2 front speakers light up, the 2 rear ones don't. I haven't found a setting that would control this... am I not seeing it or are they simply not supposed to illuminate?
That's right, only a pair comes on at a time. As I know it's impossible to reprogram it even if it's buging you a lot. You can check this article if you want to upgrade it somehow Car Audio System Wiring Basics