Problemas con el sonido de los audifonos en DDJ-RB

Sorry, I don't fully understand, even after using Google translate... Are you having problems with the playback of ONE song, or matching the playback of TWO songs?

The problem comes with the pre-listening that i’m hearing in my headphones, because the song I'm arranging to mix, sounds faster in my headphones than the sound of the master. This does not let me properly synchronize the songs, because when I think that it is ready, I upload the channel to mix it and I realize that it is slower than I am hearing it through the headset.

How / where are you outputting the sound to for the master?

The sound comes out of the controller through an RCA cable (2x2) and is connected in a sound booth.

Is it possible that the problem comes from the DDJ-RB or can it be a configuration problem for the Rekordbox?

What "sound booth" -- what is the device it's connected TO?

is connected to a speaker with two RCA inputs (black and red)

What kind of speaker / amplifier?

Something like this
https://www.linio.com.co/p/cabina-activa-12p-maxlin-450z-s1cdis?gclid=EAIaIQobChMI3_XEmozH2QIVVT2BCh3VSQLBEAQYAyABEgI6zPD_BwE

There should not be any delay or difference in speed between the same track in your headphones and over the master output from the controller. Is it possible there is some kind of audio processing on the speaker that is causing a delay?

Me pasa lo mismo con el DDJ - RB ¿cual seria la solución?

Utilice otro parlante y funciono a la perfección. Al parecer con la cabina que lo utilice inicialmente estaba con problemas. Te recomiendo conectarlo a otro parlante y probar nuevamente.