ty_ger07
If you get an external DAC, you might as well sell the Nu Audio, since it won't be doing anything that you paid it to do. The optical out on the Nu Audio is just pass-through from your CPU, and your motherboard's optical out (if it has one) will sound identical; or you can find other options for an add-on optical output card (which will sound identical) for $50 or less.
As for the interference sound, there's not much you can do other than 1) try a different PSU connector, 2) try a different PSU, 3) try a different wall outlet, 4) physically move the cards in your PC case around so that they are as far apart as possible (buy a riser cable if necessary to maximize distance), 5) enable spread spectrum in your motherboard BIOS (if disabled) to reduce interference, 6) make sure that you are using metal motherboard standoffs, metal motherboard screws, metal PCI-E slot screws, metal motherboard IO plate, etcetera to optimize grounding, and 7) try to shield the GPU and/or Nu Audio card buy whatever safe methods you can think of.
I'm still within my return window, I've had the card less than a week. Although I don't use the optical out, one of the main reasons for going with the Nu Audio was being able to use headphones and 7.1 without messing with plugs. And having a decent line-in. I might have trouble finding an external DAC/sound card that can do all of that.
Regardless, I did some testing with moving cards around to different slots. I do have a few PCI and PCI-E slots. Previous arrangement was CPU block, [free space], NU Audio, 7.1 expansion, [free space], GPU ...
I arranged it like: CPU block, [free space], GPU, [free space], 7.1 expansion, [free space], NU Audio, PSU
Now I don't hear any GPU noise in my headphones. But I still hear it in the 7.1 output. I wonder if it's distance related or if the 7.1 card is blocking the interference, and by putting an extra space between it and the main card, in turn I've shielded the main card from interference. Seems like a bit of a stretch.
I enabled spread spectrum today but the noise just sounds slightly different now.
tim62
I have a similar issue(apart from random audio stuttering /cut offs etc) that are more pronounced through the rca Output than the headphone jack. I have an nc252 amd and elac speakers that sound noticeably buzzy during cyberpunk (and still do to a degree). Switching the computer power source to a wall outlet without anything connected to it helped somewhat. I have a r9 290 and z270 i5 set up. The buzzing is even audible(way less though) through an smsl sk10 connected by usb when gaming so make sure you get an non pc usb powered dac.
I'm starting to think it's more related to the RCA outputs, actually. That might be the key. If I unplug the front speakers from my 5.1 system, the noise stops. But with the other speakers plugged in, I still get audio. There must be some kind of interference being introduced to ground because the audio to the front speakers seems to add noise to all of the speakers. I also get random cut offs that behave similarly to the audio device restarting/reconnecting. Either my card is flaking out or there's a driver issue there.
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