the weirdest sound problem that has ever happened to me, help please

Greetings.
All the usual remedies don't work.
For some reason, the functionality of my soundcard is now limited.
I can't play any media in gom player, the windows start up sound no longer plays and if I load up my gameboy advance emulator, or vice versatile commodore c64 emulator, no sound plays on that either.
I have not done any recent cumulative updates, in fact, this problem has only started an hour or so ago.
the only warning that something was amiss was when I had a computer game running, and all of a sudden, the sound just turned off.
However, I can still hear my screen reader/ Nonvisual desktop access, reading the screen to me, but it's as if all the important sound stuff has suddenly become disabled. Update: I've just tested out narrator, and that also works.
I've even gone into the sound mixer and made sure that the volume for all applications is turned up high and everything is unmuted.
I tried rebooting the machine, and that didn't work either.
Does anyone else know what might have happened?
windows 10 pro.

Yikes. I feel really foolish now.
It was my screen reader, NVDA which was the culprit.
somehow, a setting had been changed to rout the screen reader to one channel, and all the miscellaneous sounds, like GOM media player and computer game sounds to the other channel. whew! glad I got it fixed!

- - - Updated - - -

wow. I knew there was a simple explanation, but I couldn't for the life of me think what it could be. This problem kept me up for hours, but following a hunch, I went into my screen reader's configuration and fixed it.
and just in time for my Birthday too.

whocrazy said:

Yikes. I feel really foolish now.

*points and laughs*

...because I totally never did anything like that! Nope, never tried to use my microphone to chat with a friend during gaming and spent 30 minutes trying to figure out why it wouldn't work, only to find out the privacy settings were Mic = Off! Nope, not me. Never happened. At all. Not even a little bit.