There is no change even if the [CAPTURE] button is pressed while pressing the [SHIFT] button.

1. Is the slicer or slicer loop mode set?

Press the [SLICER] mode button to set the slicer mode, or press the [SHIFT] and [SLICER] mode buttons to set the slicer loop mode.

2. Is the sampler slot that has been already loaded selected?

Clear the sampler slot by clicking the [EJECT] button on the sampler panel of rekordbox dj, or select the [SAMPLER] tab on the [Preferences] > [CONTROLLER] screen of rekordbox and unlock [Eject/Load Lock].