Are your meters lit up with good, strong levels around 0dB? If not, then you’ve likely forgotten to route your channels anywhere. Engage one of the assign switches next to each of your faders: LR for main mix and 1-2/3-4 for subgroups (which can then be routed to the main mix). The mixer won’t assume you want signal to go anywhere, so make sure you let each channel know where you want it to go!
For more information or questions about Mackie products, please contact us here.