(To make a long story short, I needed to test if a problem on another system was due to the headset I was using, so I unplugged the headset on my PC (which played sound normally up until then) and when I plugged the headset back in I found that I couldn't hear any sound.
So far, I have (in no particular order)
1: Checked to see if I am plugging the headset in correctly... but just to be sure the pink headed wire goes to the pink plug, and the green one goes to the green plug (same shade of green), right ? The pink one even has a little microphone icon on it...
2: I tried removing and reseating the sound card itself
3: I checked the volume controls (although I didn't change anything, I just unplugged and replugged the headset). Volume Mixer seems okay (the volume isn't muted- HOWEVER, I have noticed that there are no green bars indicating activity whenever I play anything, which should be the case if the problem is my headset, right?).
4: Likewise, I checked to make sure the correct device is "default". It is.
5: I checked to see if somehow the default device was switched. It wasn't.
6: I checked in device manager to see if the device was somehow disabled. Nope. Likewise I checked the settings and the sound output isn't muted.
7: I uninstalled the driver for my sound card and reinstalled it.
8: I tried unplugging and replugging the headset itself (It's a turtle beach headset that needs usb power, could that somehow be playing into this? I tried switching which usb port it is plugged in to, but again, the volume mixer thing seems to indicate that the headset is not the problem).
9: I tried unplugging and replugging the little miscellaneous cable-of-mysterious-purpose that goes from my motherboard to the sound card.
10: Of course, I tried multiple sources of sound (youtube, various windows sound tests, a video).
11: Just for the hell of it, I tried the two optical ports (I have an old-but-still-functional Astro Mixamp). No go.
12: Checked in device manager. The ever-helpful device manager said (as it always has as far as I can remember, for anything and everything that has ever malfunctioned on every computer I have ever owned or worked with) that the sound card is "working properly".
13: I tried sacrificing a Ewe to Pan the goat god (not really, but I'm getting there. And yes, I know that a Ewe is a sheep, and Pan isn't--- actually we're getting off topic here ).