Question Static with headset speaker in DAC and microphone in PC

[Morfi717]

Hi.

the setup is as follows:
- PC with mobo soundcard, 2 front and 6 back jacks
- USB DAC with speaker out only (no mic)
- headset with single jack + jack splitter (speaker/mic)
- external USB sound card with single jack in
- jack 'merger' (from speaker/mic jack to single jack)

DAC supports just line out so splitter for headset is used to plug speaker jack to DAC and mic jack to PC

The issue: whenever I plug in mic into PC I hear static in my headset speakers as well as people on discord would hear the static

I'll use following abbrevs below
S = speaker jack from the splitter used in headset
M = mic jack from splitter used in headset
D = DAC plugged in to the PC via USB
SC = USB soundcard with single jack in

Static occurs when:
S -> DAC, M -> PC front
S -> DAC, M -> PC back
S -> DAC, M -> jack 'merger' -> SC -> USB PC

Static doesn't occur when:
S -> DAC, M -> jack 'merger' -> iphone
S -> PC front, M -> PC front

It seems that if I don't use DAC, there wont be any static. But if I do use DAC (which I want to) then however I plug in mic to the PC (be it via mobo soundcard or through external usb card) then the static will occur.

Its worth notic that if I'm using external USB sound card where I plugin in the mic (while the soundcard is not plugged to the PC) then if I even barely touch the USB port the static will happen -- I don't even need to plug it in or even slightly insert it in the port.

Should this be important then my tower is corsair obsidian 750D, PSU is be quiet Straight Power 10 and the PC is plugged to a different power plug than other peripherials however they'll share same coord (in the wall). I'm just mentioning it should this issue had anything to do with how power is distributed or whatever. This doesn't matter as I tried on two notebooks with no AC, same story

Thanks

 

[NewYears1978]

Did you ever figure this out? Apparently it is a common problem. I have the same issue and I cannot figure out how to solve it other than buying a USB sound card or a USB headset, which I want to do neither.