Is it possible for you to make a recording of the sound, either a video of it occurring, or even just audio of it occurring? This would serve two purposes.
1) If the recording of your gameplay doesn't have the pop-and-crackle, it's another piece of evidence that can be used to troubleshoot (in this case it would be proof positive of no issues at your audio ports, no cabling issues, no bluetooth interference, etc.); and
2) Hearing the distortion can help quite a bit in diagnosing a problem. Kinda like when you tell the mechanic that your car's going 'clunk, clunk, screech' ... it doesn't help much until the mechanic can actually hear the noise.
Upload info to your choice of video host, audio host, whatever works for you, and put the link here, if possible.
- I know you said you've tried many different physical setups so #1 above may seem redundant, but any evidence is useful.
- Setting sound quality to a low level in Windows isn't likely to have any effect; feel free to return those settings to normal.
Do check this, though:
- Right-click your speaker icon in your system tray, choose Sound Settings.
Then, for each device you are using (under "Choose your output device"):
- Click "Device Properties" -> "Additional Device Properties" (on the right).
- Check the "Enhancement" tab and temporarily choose "Disable all Sound Effects".
(Features listed under "Enhancement" vary by device and driver, but you generally don't want any "volume boosters" active, as those will clip sound and cause pops and crackles. You also don't really want any 'Environments' or 'Virtualization' or 'Virtual Surround' (not for testing purposes, anyway), and if you have an 'Equalizer' enabled, you'll want to make sure your settings there are subtle (no sliders maxed out) as large corrections via an EQ often also cause clipping/popping. Better to just try with EQ and everything else off; you can return sound settings to your preference if the changes have no effect.)
- Under the 'Advanced' tab, anything at or above 16-bit / 48,000Hz will give you great sound quality. Values above 16/48k are argued over widely, but of little audible effect to the average user. Nothing you could choose here would cause "popping" or "crackling", so feel free to set this value where you like, but note that values below 16-bit or 44,100Hz will diminish sound quality.
- Also under the 'Advanced' tab, your 'Exclusive Mode' options should both be checked, though having these options either enabled or disabled wouldn't cause audio cracks and pops.
Good luck!