Sometimes the unmuting doesn't work, but that's not that much of a problem because I only need that when I'm on that tab.
Otherwise it works very good and provides a feature that's unfortunately missing in Firefox.
Sadly the addon doesn't seem to be further developed anymore.

sound playing somewhere in my 200 tabs in 30 windows. Loaded this addon. Clicked on its boombox icon in the toolbar. Immediately told me which tab it was. Clicked on the tab shown. It brought the window to the top but did not display it. It was still under my current window. I had to hit Alt+Tab Alt+Shfit+Tab once to get there. I could have minimized my current window also. But so easy. Thanks. Works.

Sound Control de kumar303

Great extension! only there are not enough functions for controlling the sound level, play-pause, and a preview picture for the media being played. maybe something can be used based from them: https://addons.mozilla.org/ru/firefox/addon/sloth_music_controller/?utm_source=addons.mozilla.org&utm_medium=referral&utm_content=search
https://addons.mozilla.org/en-US/firefox/addon/pin-video-controller/
https://addons.mozilla.org/ru/firefox/addon/media-controller/?utm_source=addons.mozilla.org&utm_medium=referral&utm_content=search

Works as advertised, no negative side-effects, source code on GitHub... What's not to like?
And what more do you want?!

Ummm, now that I've asked: How about a white icon to switch to? Ya know for themes that need it. Looks very jarring if SC's icon is the only black icon in a row of white ones.

Works great but would LOVE to also have a volume slider/controller for all sources or just one to control them all. Like this add-on on chrome "Volume Controller".

I grew up with one. This 1 I ran with. It's alive. Functions exclusively. Awe,....the recall. hahaha :)

This add-on works and does what it says