My Firefox is having some problems relating to audio. If I open a YouTube video, the image will play but there's no sound, on Twitter also, and so on. On YouTube Music the player won't even start, giving the error "An error occurred. Please try again later." I noticed that '''the stereo icon that shows up in the tab, which allow you to mute the tab, won't show up''' when I'm playing a video on YouTube, Twitter, Vimeo, and so on. Only Firefox has no sound, it's not muted in the Volume Mixer, neither in the app volume settings in Windows. I've followed everything suggested here [https://support.mozilla.org/en-US/kb/what-to-do-if-firefox-wont-play-any-sounds here] and [https://support.mozilla.org/en-US/kb/fix-common-audio-and-video-issues here]. I think the problems may have started after I reinstalled my graphic card driver, but I'm not sure since I don't use this computer very often. I have a Windows 10 and my graphic card is a Nvidia GT 630, and the driver version is 474.44.