To do this, start by switching off the DJM-A9.

1. Then switch it on while pressing the [QUANTIZE/UTILITY (WAKE UP)] button.
2. The [FACTORY RESET] screen appears. 
3. Turn the [TIME] knob in the Beat FX section to select [YES], and press the [TAP] button. 
4. You must now switch the DJM-A9 off and you then can turn it on again.