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Click the MASTER button up at the top-right of the rekordbox window:

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Hello guys,
When first connecting my DDJ-RX I was asked what speaker setup I'm using. Problem is I have mistakenly selected that my speakers are connected to my laptop but the truth is they are NOT, they are connected to the DDJ-RX and laptop at the same time.
If I go to Preferences - Audio I can see the Master OUT feature but the field is disabled and the button labeled Settings Utility does NOT work. What can I do?
Thanks in advance!
Click the MASTER button up at the top-right of the rekordbox window:

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Worked like a charm, thx Pulse, you the man!
Awesome - thanks for writing back to confirm. :)