Mackie D8B3.0 Owner's Manual page 108

This simple checklist will help get the mix started.
Notice that, each time, we follow the signal path
from its source to its destination.
Pressing DIGITAL TRIM activates the channel
V-Pots as digital input trim adjustments.
Digital clipping could occur if a signal going
into the D8B is too hot. Noise could occur if the
signal is too low. Even though the D8B has plenty
of headroom and very little noise, it's still a good
idea to verify optimum levels.
If the outputs from the mixdown recorder are
patched into the D8B 2-track or Digital inputs,
simply select the mixdown recorder in the Control
Room Section (Digital 1, Digital 2, 2 Tracks A–C).