Yes, I am having the same issue. Its only when the video card is being used heavily in gaming (evga 1080ti). But its extremely annoying, I've tried all slots distancing the 2 cards helped slightly but I don't have any other fix yet.

I don't have any with really high impedance, running Sennheiser 598 cs 23ohm. After messing with it more yesterday, I moved the cards as far as possible apart its a lot better. Only time I hear it badly is when moving things around, like my browser, on my second monitor. 

Yes, I tried that as well. Figured that would be a good place to start, i have modular power supply and it has 2 completely separate 12v rails, I tried splitting them and had no effect. Like i said before the best thing I did was move them the farthest away possible. Problem is now, I am using 3 monitors, my 2 side monitors are older monitors and only have DVI inputs, so i am running a second video card gtx670 for the outputs and that card is much closer to the NU audio card so I get a lot of static when moving things or using my 2 side monitors.  

EVGATech_LeeM
Just checking here, but are you all using the SATA power on a cable directly from the PSU, without anything else attached to the cable?

(sorry for the late reply) Yes, I am using a dedicated SATA cable. I am not so sure this is an issue with the NU Card as much as its an issue with the EVGA GPU... Unless its an issue with the power supply its self which would not surprise me as I keep getting post code 97 on cold boots in the mornings.