No audio output when DDJ-WeGO4/DDJ-WeGO3 is connected.

Check the followings according to the audio you are monitoring.

When monitoring MASTER output
　-Check the MASTER LEVEL.
　-Check the CH FADER of the playing deck.
　-Is the CROSSFADER on the playing deck's side?

When monitoring PHONES output
　-Check the HEADPHONES LEVEL.
　-Is the HEADPHONES SELECT button turned on?

In both cases
　-Isn't the PLAY/PAUSE button tapped to PAUSE?
　-Isn't the TEMPO -100%?
　-Aren't all the EQ knobs turned fully to the left?