Strings flash randomly

[btm231]

I'm about to just throw everything in the trash at this point because I'm losing my mind...

Using pucks from Ray Wu that I intend on hanging with tracks and trying to test before I deploy them, but any time I run a sequence with everything hooked up to the F16, I get these random flashes across all the strings. Voltage is fine, animations look great, but this flash persists and there's no pattern to it. The flash also presents itself when starting a sequence manually within FPP. I don't know if the board is faulty, the software, or if something else just isn't playing nice.

I have a DigiQuad lying around from a different project and decided to try running the strings off that to rule out faulty strings, but I don't have the problem there... so something is up with the F16.

Any ideas where to look? Do Falcons just hate my strings? Do I have a bad board?

https://imgur.com/a/JHhldYu

[tbone321]

Make sure that XLights is not running and set for output to lights. 

[btm231]

Yep, this is happening while strictly playing from FPP without Xlights open.

 Got a smart receiver today and have been running them off that and still the same issue...

What's worse, I've been playing with playlists and it happens almost every time the next effect plays too!