Asus Maximus VIII is a very good motherboard, but terrible for audio. Asus forums are really full of complaints about it because it emits pops and clicks now and then, so consider yourself a lucky boy if yours does not exhibit this issue, ZedZedski
I think MSI is the safest solution for Z170, at the moment: that's at least what I'm suggesting to friends of mine, lastly. It's a pity, because on the paper Gigabyte's motherboards are superior both to Asus and MSI. If it weren't for this terrible audio implementation...
(Oh, incidentally, it's true that the mouse in BIOS, on Gaming 7, is laggy, but only if you don't update the BIOS to latest release).
That said, I'm on my
18th day without no more a single problem with the audio on the Gaming 7 (*crossing fingers*). What did I change, you ask? Simple: I disabled
ALL the Windows enhancements
AND ALL the audio enhancements in Creative panel too, both for playing and recording (including Crystal Voice, alas).
Sure, audio quality is worse than with the enhancements on, but still good for my 2.1 speakers and my HyperCloudX headphones.
If it'll continue working fine in the future days, it means that the audio problem resides certainly in drivers (poorly coded by Gigabyte crew) and is not hardware-related.