No Sound on rekordbox performance mode

I just got my DDJ-RB and connected to my speakers. (MAC)

In export mode, I could play songs through my speakers.

But in performance mode, when I click songs in software, I could hear the sound in my headphone which is connected to DDJ-RB.

I could use controller to load the songs and control them, it showed on my laptop screen. Once I loaded songs to the deck and played, there's no output sound either from my speakers or headphone.

I installed the latest drivers and software, and it seems nothing wrong in my configuration.

What's the problem?

Btw, now I use my RCA cable connect to my sound bar analog input.

Thanks