Each deck on the SDJ-4000 can play in two different modes: VINYL mode ON or VINYL mode OFF. Use the VINYL button under each jog wheel to switch between modes. When the button is illuminated, the deck is in VINYL mode; if not, then VINYL mode is OFF. Both modes will allow you to pitch bend (temporarily slow down or speed up the track) with the jog wheel, but there are several key differences.
With "VINYL" mode ON, the playback will pause when you touch the top of the platter; this is to emulate a vinyl record on a turntable. This also allows for "Scratching" via the jog wheels. (Touching the top of the platter will do nothing when VINYL mode is OFF)
If VINYL mode is turned OFF, when the track is paused, you will hear the audio from the exact location of that deck's playhead repeatedly on loop, allowing you to easily find a downbeat for cueing by moving the JOGWHEEL forward or backward to move the playhead. (You will hear nothing when the deck is paused in VINYL mode.)