RB won't play a track, but the waveform moves as normal

I just got a DDJ-1000 and key for RB hooked up to a MacBook Pro (13-inch, 2017, Two Thunderbolt 3 ports)

A large portion of my track, say 30% will load into a deck and I can control them as normal, but RB doesn't output any audio. Here's what I know: 

• The tracks it won't play are persistent, meaning Track X will never play even if I quit, or reload a deck or move to a new deck. 
• I doubt it's the DDJ-1000 as RB won't play Track X either through the DDJ-1000 or the PC out, or when the controller isn't even connected.
• The tracks all work in Serato, Traktor, DJay Pro and iTunes
• I CAN hear the tracks in my headphones when I click on them in the playlist to do the pre-cue thing. 
• Changing bitrate is no help
• I have a few full albums tht some tracks will play and some won't. So I don't think it's the MP3 encoding. 

I made a video that I think demonstrates it. Youtube rotated it 90 degrees and won't let me rotate it back... not my week for tech)

Any bright ideas? i'm thinking re-install RB, but that seems like a pain. 

Thanks!

Martín