Your SDJ-4000 has a SCRUB strip below the JOG WHEEL that allows you to move the playhead around your loaded track.

To utilize this function, hold down SHIFT while gliding your finger along the SCRUB strip. You will see the playhead move around the track's waveform display. When the locater is where you'd like to move the playhead, release SHIFT, and the playhead will snap to its new location.

Product: SDJ-4000