Did you try these firefox help yet.

https://support.mozilla.org/en-US/kb/what-to-do-if-firefox-wont-play-any-sounds https://support.mozilla.org/en-US/kb/fix-common-audio-and-video-issues https://support.mozilla.org/en-US/questions/1323720

None of those are even remotely close to my issue. If I'm on a website for communication purposes, audio should come out my headset. If I'm on other websites, audio should come out my sound system. From what I can find, there are no sound or audio settings in the firefox settings. I can manually change the output through windows, but that puts all audio out of whatever output I selected. It works right in literally every other program. Period. Even CoD, which is saying something because that games VC is straight garbage.

Sound Master control is through the O/S not the browser. If you plug into the headphone out on the computer the O/S will switch all Audio to that port. That's how mine work and if you have a Audio out system then plugging into that Audio is how you get your sound to headset otherwise you will have to plug into the Computer Audio out to the sound through the headphone. I know my nephew has a USB gaming headset and he can plug the USB Audio out and play sound straight to the headphone or computer speak if he unplugs the USB audio device. So until someone is there to hear the Audio setup no one can know what is going on there.

And yea, all that is fine and dandy, except, you know how when you're playing a game and talking to people and the game sounds are coming out your sound system and your friends are in your headset? Because the purpose of a headset is so you can hear your friends over the audio. If the game audio (in this case, websites like YouTube, Netflix and the liked) is coming out the headset as well, it defeats the purpose, but that's exactly what firefox does. For context I have a USB headset. And like I said, literally every other program knows what audio is for communication and what audio is not. And yes, in Windows I have the headset set to be the default communications device, and the sound system to be the default playback device. So, why Firefox chooses to ignore this is beyond me. At this point I'm just gonna create my own browser because google is a crappy company, and apparently firefox is developed by and maintianed by a bunch of incompetent programmers. If Activision can figure out how to make it work in their games, as bad as they are, and Chrome was able to do it no problem, I don't see what the issue is. I can't tell if you're just plain stupid or ignoring the problem because it can't be fixed.