There are three possible causes.

1. Is [FADER START] set to [OFF]? At the [USER SETUP] screen, set [FADER START] to [ON]. Also set the [FADER START] button on the control panel to [ON]. For details, see “Setting preferences” in the operating instructions.

2. Is the DJ player properly connected to the [CONTROL] terminal? Properly connect the DJ player to the [CONTROL] terminal using a control cable. For details, see “Connecting input terminals” in the operating instructions.

3. Are the audio cables properly connected? Connect the DJM-850’s audio input terminals to the DJ player’s audio output terminals using audio cables. For details, see “Connecting input terminals” in the operating instructions.