Audio devices disappear after failed update

My computer (i7-6700K, ASUS Z170-Deluxe, 16MB ram) was working fine until it tried an update to KB50003637. During the update, it BSODed with a PAGE_FAULT_IN_NONPAGED_AREA error, after which it notified me that the update had failed and attempted to return to its previous state. However, when Windows restarted, I was getting a red X over the speaker icon on the taskbar, along with "No audio output device is installed" and "Speaker Setup (UNKNOWN)" messages when you hover or right-click on the icon, respectively. Running the Audio Troubleshooter only tells me they're sorry that they couldn't fix my problem. I've been using the standard on-board Realtek High Definition audio, and first tried reinstalling the driver, but the problem continued. I checked Device Manager, and both the "Audio inputs and outputs" and "Sound, video, and game controllers" sections had the Realtek device listed, along with the comment that "The device is working properly." I then tried a installing a USB DAC (LH Labs Geek Out 450) I've had sitting around for some time, along with its driver software. Same problem: that device is "working properly," but Windows itself still gives the red X and "No audio output device is installed," etc. messages. Now, this USB DAC has an ASIO driver as part of the software, and apps that can use ASIO (Foobar2000, JRiver Media Center) can be configured to use it via ASIO, and can play audio through it just fine -- but, at the same time, according to Windows, I don't have any audio devices, so none of the programs that don't have ASIO support (the vast majority of them) can't play audio on my computer at all.

Needless to say, I made repeated efforts to reinstall the drivers, with no success. I also repeatedly uninstalled the devices and restarted, but, after the restarts, I had the same devices in place, all "working properly" according to device manager, but unavailable through Windows. I also tried stopping and restarting the "Windows Audio" and "Windows Audio Endpoint Builder" in Services, but that didn't have any effect either.

I checked out the details on each of those drivers in device manager, and found both of them were reporting that the devices could not be migrated because of "due to partial or ambiguous match."

The Realtek device had the following error message in "Events":

Device HDAUDIO\FUNC_01&VEN_10EC&DEV_0900&SUBSYS_1043868F&REV_1000\4&27952083&0&0001 was not migrated due to partial or ambiguous match.

Last Device Instance Id: TUSBAUDIO_ENUM\VID_2522&PID_0007&KS\00000040
Class Guid: {4d36e96c-e325-11ce-bfc1-08002be10318}
Location Path:
Migration Rank: 0xF000FFFFFFFFF132
Present: false
Status: 0xC0000719

while the LH Labs Geek Out had:

Device SWD\MMDEVAPI{0.0.0.00000000}.{8cb2f8d3-e308-4d89-b3e6-84c96dc89425} was not migrated due to partial or ambiguous match.

Last Device Instance Id: SWD\MMDEVAPI{0.0.0.00000000}.{1b978cd4-4584-49a4-a00b-b64c043eccc1}
Class Guid: {c166523c-fe0c-4a94-a586-f1a80cfbbf3e}
Location Path:
Migration Rank: 0xF00000000000F100
Present: false
Status: 0xC0000451

Can this give any clue on how this problem can be fixed? I've tried every "standard" step for such problems, and am completely at a loss right now. Is there a way I can get back my audio without having to take the drastic step of a clean install?