So this weird issue started to happen to me today. I have three sound outputs which I switch between depends what I'm doing.
1. Monitor speakers ROG PG279Q connected via DP.
2. External DAC connected via USB for my gaming headphones.
3. Oculus Rift's headphones.
Now the problem I started having today is that when I switch output to Oculus Rift or external DAC and have sound on my headphones my monitor speakers starts outputting laud cracking noise (nothing else). Sound I have on my headphones is fine. It's like some cracking is being leaked to DP's sound channel and outputted via monitor. Funny thing is that this cracking depends on what I'm doing on screen so it cannot be some weird electrical interference.
I don't even know if its Win10 fault, mobo, integrated sound card/driver or something else. Before all was fine.