From MOD Wiki
The graphic below represents the signal-flow of the audio inside the MOD Duo.
Please note the position where the LED meters read from.
The LED colors represent the following input levels:
- Off: below -30dB
- Green: between -30dB and -12dB
- Yellow: between -12dB and -3dB
- Red: above -3dB
- Blinking strong red: 0dB (CLIPPING!)
- The input gains accessible via the menu - both stage and fine adjust - determine the level of the analog signal coming to the ADC. This is 100% analog.
- The output volume accessible via the menu does not affect the running pedalboard and can't help in case it is clipping. You can solve clipping by reducing the volume inside the pedalboard.