Several serious problem with Rekordbox. URGENT!

Hello friends.
I'm having a big problem with Rekordbox.
I bought the DDJ-RZX and got a MacBook Pro 15 retina with 16GB of RAM, a 2GB video card, Apple's top line purchased in 2015.
The problem is several, starting with the fact that on several occasions he closes alone leaving me with no alternative, stopping the sound. When this happens it creates a LOG file.
Another serious problem is when you are running a video and add another video on the second deck, the sound fails and gets totally distorted and slow as if you were missing memory.
I'm embarrassed and I do not know what to do anymore.
I have already optimized my MacBook to run rekordbox, I leave nothing open when I am playing but the problem persists and seems to be getting worse and worse.
I'm seriously thinking of selling my DDJ-RZX and getting back to Serato that has never given me any kind of trouble.
I consider my MacBook a machine of high performance and performance, since it is the top of the line Apple. There is no better configuration.
What should I do?
I need help urgently!
I await your return.

Att,

Dide Gemignani