Hi Antonio, I moved your question to the right forum and changed the topic to something relevant.
As for Rekordbox, there are a lot of manuals and video’s out there to help you with that one. But perhaps one of our other readers will give you a heads up on this.
Linking two CDJs together is done by “Link”-cable, effectively a regular network cable. Depending on your setup you might need a (wireless) router as well. Pioneer has a complete manual on using the Pro-link feature. You can find it here: http://pioneerdj.com/support/files/img/DRI1124B.pdf.
Finally, starting a track by using the channel or crossfader is something that needs the setting on the mixer. Depending on your brand/model of mixer you might need to run a cable from the control output on the player to the control or faderstart input on your mixer.
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