Asus Maximus VIII Hero Popping Sound on boot

No problem with mine - have you benched it to see if it might have anything to do with the case? Have a guide that may help:

http://www.tomshardware.com/faq/id-1753671/bench-troubleshooting.html

Let me know how it goes, I'll be in and out

I've been having sound issues with the Maximus VIII Hero Z170 as well (popping, warbling, etc.) However, I have managed to solve my issues. Maybe this will help you. I looked into Device Manager (under Sound, Video and Game Controllers) and noticed there were multiple sound drivers (such as Realtek High Definition Audio and NVIDIA High Definition Audio). I read elsewhere there could be a conflict with respect to sound drivers. Like you, I happen to own an NVIDIA video card and my understanding is the NVIDIA sound driver is loaded when you choose Express Install for your NVIDIA video card driver (as performed using the GeForce Experience software interface). So -- to start from scratch -- I uninstalled the NVIDIA video driver and the Realtek sound driver. I rebooted and everything works fine. Of course, this means I'm just using the motherboard's own integrated video at this time. Don't worry. This is just temporary. Next, I reloaded the Realtek sound software. When complete, I went into Control Panel, Hardware and Sound, opened the Realtek HD Audio Manager to adjust my speaker configuration and indicate I had a 2 speaker setup. For some reason, it automatically selected a 7.1 speaker setup and I was losing a channel when playing back videos or when gaming. I performed another reboot and validated sound performance was good. No pops or crackles. Finally, I reloaded the NVIDIA video driver using Custom Installation. I ONLY loaded the video driver and unchecked the 3D options (i.e. 3D vision/3D PhysX) and the NVIDIA High Definition sound driver. I rebooted and looked at Device Manager again. It looks like NVIDIA still makes an entry in Device Manager. What I see is the following: (i) NVIDIA Virtual Audio Device (Wave Extensible) (WDM) and (ii) Realtek High Definition Audio. So I manually disabled all items except (ii) - (the Realtek High Definition Audio driver) by right-clicking on each item and choosing Disable. After another reboot, I played a video, music and a game. So far, everything is working fine now. I hope this advice will solve your sound problems with sound for this board. NOTE: I suppose I should add that I installed the Realtek audio driver obtained from the ASUS support website for my motherboard. There is a more recent driver at the Realtek website. I tried it and still had problems so reverted back to the driver found at ASUS. At the time of this writing, this would be version 6.0.1.7629. I'll keep monitoring the situation and post updates if I run into any problems. It may be too early to say this is the definitive solution to the problem.

Hey don't worry! I have this popping sound aswell on my VIII Ranger. It makes the popping sound because you have Fast Boot enabled, if you disable Fast Boot, it will not make the popping sound anymore. I don't really care about the pop so I leave Fast Boot on.

I also have the Asus Maximus hero VIII and hear this click once as I boot up and once I shut down. If you disable the onboard sound the click goes away. From my understanding its a relay turning the onboard sound off and on. And totally normal.

This still doesn't change my opinion about this sound. I freakin hate it. Just got done with a new build and it has this generic click. like a cheap plastic toy sound