no audio through speakers or headphones -DDJ-SZ2

Hi there,
I just purchased an SZ2 controller today. I'm using a Macbook Air with the El Capitan OS. I downloaded both the firmware and Serato software. I have Rockit 6 speakers plugged in, and I've tried using both RCA and the other type of connection at the same time, and also plugged the Master 1 and Master 2 connections in separately. I'm using Audio Technica headphones.
After loading a track onto one of the decks, I can see the waveform but there is no sound playing and the indicator lights are not lighting up. I have messed with the cue buttons, master volume, trim, and fader level. I've looked at many help forums and FAQs and still cannot get audio to come out of the headphones or the monitor speakers. I have made sure that the output and input are set to default in my System Preferences, and checked the Midi Audio utility as well. I simply cannot figure out what I'm missing or doing wrong. Please help!
Thanks,
Kenna