So in the past 3 days, I've gone from having audio and using my headset to communicate on Steam or whatever, to no audio playback or input at all.
I first noticed an issue after using Mumble for the first time, though I'd installed it over a year ago. When I used it, everything was fine, but the day after I used it, I couldn't get my microphone to work. I also didn't have sound coming out of my computer at first, but I uninstalled and reinstalled the driver for my soundcard, and it worked fine for that day. The next day, nothing worked at all. Under Sound in the control panel, it says "No audio devices are installed." Under Device Manager, I saw my soundcard, and onboard sound, and all of these say "The device is working properly."
So I reseated my soundcard, and got no improvement. Then I took the soundcard out entirely, and uninstalled all drivers and software, and still have no improvement. With onboard audio only, it still says "No audio devices are installed" under Sound from the Control Panel, though I still see the devices and they are still "working properly" under the device manager.
Any ideas for where to go next? I can't think of what the next step could be.
For reference, the soundcard is a Soundblaster X-Fi something or other that I've had for 6 years, and the computer is one I built last year which got the soundcard from a previous machine. Until this week it worked perfectly. Also, I'm on Windows 10, though I was on windows 8 when it started and I thought upgrading might make some kind of difference, though it didn't change anything. I also got a mechanical keyboard, a Ducky Shine 4 this past weekend, but that doesn't have any related software.