PC Freezes when I change the fan controller settings?

I built a PC about a month ago (see it in excruciating detail here). The key components are:



Fractal Design Define R4 case (built-in fan controller)

EVGA Supernova 750 G2 PSU

AMD FX-8320 @ 4.0 GHz

ASRock 990FX Fatal1ty (Killer) motherboard



I am running the CPU Cooler fans (Phanteks PH-TC14PE) through the motherboard headers, but I use the R4's built-in fan controller for the case fans. The title is the story - if I change the fan controller position, the computer freezes. I rechecked my cabling, which is fine, and the only way the controller is connected to anything besides the case fans is through the PSU. It uses a Molex connector. I can't fathom what would cause this to happen, it's just a fan controller.



I noticed the behavior from the start, just didn't worry about it and hoped it would go away. It didn't. I have since noticed that it seems to happen more when I turn the fan voltage up than when I turn it down - not that I've done a lot of testing, because I don't want to hurt anything. This is not a major workflow issue, but slightly worrisome because I don't know the cause.



What might the problem be? Should I be concerned? Should I just restart my computer if I plan to turn up the fans? If I need to RMA something, which thing is it?

PC Freezes when I change the fan controller settings?