Problem with input on off switch light.

On my Zoom 16D recorder, I am in 8 track simultaneous mode. I'm using three tracks. The on /off switch will only light up red for two of those inputs. The input is active when I press the switch and the signal shows on the led meter for that track but the red light doesn't come on and the little peak light for that track doesn't come on when you turn the gain up. I record and that track records. Seems like it's just the light of the on/off switch and the peak light are not happening. The tracks I'm recording on are tracks 2, 3 and 4. I have a cd player in tracks 7 and 8. Everything on tracks 7 and 8 are fine. Track 1,2 5 and 6 will not go red at the input switch. Help! The status keys are fine all around, I think. Not at my machine right now. Any assistance would be greatly appreciated.