LIVE Event Audio not sync with BOINX Video

I was doing a live event where I am using BOINX to only mix the video, not have anything to do with the audio (unless I’m playing back a video from BOINX). I’m not recording to BOINX. Just taking the BOINX and putting it up on the big screens. The sound from the stage mics is going straight to the sound system, never goes near the Mac. I realize that this might already answer my question, but I’m having the sound and the video out of sync this way. It happened with two different setups – one on a 2006 MacBook Pro (15") and the other with a 2012 MacBook Pro (15"). The audience could see the missing sync clearly. Anyone have a suggestion for making the two come together?
(I’ve thought about running the house mix into the Mac and then back out again to the amps/speakers – which creates a wiring nightmare.)

The cameras and BoinxTV take a while to process the signal. With the sound going right into the sound system you don’t have the same delay here. So either get a delay unit for the sound to match the audio and video delay or run everything through the Mac.

x2 the audio needs a delay. you can do it with boinx, I have to with mine (HDMI source Cam via Intensity Extreme & a Blue Yeti Mic via USB, it’s about a .35 sec delay in the BoinxTV pref pane for the mic.

I’ll need to try this out, cuz I suspect that the .35 delay could cause the audience closer to the stage to notice the delay. I’ve got until May to figure this out. Thanks for the responses.