■rekordbox for Mac/Windows
When PC Master Out is turned on, you can output the audio from your PC/Mac's speaker.
■rekordbox for iOS/Android
When using a USB connection, sound doesn't output from your mobile device.
When using a Bluetooth connection, sound outputs from your mobile device.
When using a USB connection, sound doesn't output from your mobile device.
When using a Bluetooth connection, sound outputs from your mobile device.
■Serato DJ Lite
For details see the Serato DJ Lite manual, available from the Serato website [serato.com].
Please refer to the manual and change the settings to output the audio from your PC/Mac's speaker.