LED control for the ADAU1401EBZ eval board

Does anyone have a sample file of how this might be done? I am trying to achieve a simple result with the ADAU1401EBZ eval board, but currently all four LEDs are always on, even with no audio input signal.

I need to trigger the LEDs on MP-8 and MP-9 for signal presence on left and right audio ins respectively. I also need to be able to adjust the threshold of that signal level which causes the LED to light, somewhere within a range of -40 to -10dB.

Thanks,

AL