No, the red power wire should be on in either Accessory or Ignition On positions. The yellow is the constant feed to maintain settings and time. If either interrupts, the unit lights will flicker and that is not happening. So I don't think that is the problem. If it is not the speaker wiring, which may be triggering a safe mode shutdown, which leaves the light on, then I'd say the unit itself may be defective. Sure would be nice to swap in another one to see.
