Interesting. Alan modifies 'RTKVHD64.sys' (I believe with 5.1 mods, based on tests), when I used it with the DTS encoder, I also got noise although subtle.
You could call it subtle, you could also call it terrible, it's a really unpleasant digital noise, and completely unpredictable how loud it's going to be the next time, it takes me totally out of it when listening to music especially.
I now have installed only the Dolby Digital option, not because it's what I want, i want DTS, but I figured maybe something would change, and indeed the clicking/ crackling noises are still there but from half an hour testing i think i can say it's a lot more silent and not as annoying. Sound quality overall is definitely worse, but that's at least something
But, I still have this thing that it'll always show decode when I play music, which it really shouldn't and never did when the original Realtek/ Microsoft drivers were still working, it only switched to "dolby" or "5.1 decoding" when there actually was a 5.1 signal, so that is weird, and from my limiting testing so far positioning in games isn't as clear as I'd like or was used to, not sure why.
I do think it's mostly windows messing around, but who knows maybe drivers are just "unstable".
Trust me, I'm definitely glad I found this solution here, but I'm also thinking maybe using the original driver with the patch would have better results, although I can't know, maybe it's just as inconsistent.
Note to @Alan Finotty, you might need to use the original 'RTKVHD
Maybe you're onto something...! @ Alan I'll give that new driver a try after I tested this one i have right now a bit more, thanks, here's hoping!