works well on the sites it's allowed to except for twitter with mono videos, the mono convert feature doesn't work for me. no sound no matter what.
(i'm using 7.1 surround in windows)

It would be nice if i can access this feature from Right-Click menu on specific media/video, cause most of the time i don't know which control for which video on website with a lot of videos in one page, like facebook

SoundFixer works well on non-cross-domain sites so I can hear what's going on through my not state of the art speakers. Unfortunately, when I leave a site after using SoundFixer, the volume level is reset very low, so the next time I go to a cross-domain site I'm up a crick and can't hear a thing.

Works really well, but does not work with the add-ons "Faster Video" :( if he starts to cooperate, he gets 5/5

The extension delivers what it promises. However, you lose the playback speed option when you use this extension. It's not the end of the world, but it is dissapointing. If it allowed playback speed changes it would be perfect.

Its a great fix for a better sound in firefox. I wish it could had an option to set the gain control by default to a louder one

Awesome extension that fixes the poor sound volume of my 2011 MacBook Pro. I would give it 5 stars, if it were to permit speed controls. Currently, it always resorts back to 1x speed for videos when changing the gain.

Ookoo

Great add-on, my only complaint is that moving the sliders from their default positions prevents YouTube's playback speed controls from working (reverts speed to x1).

d

A life saver in many situations.
Sadly, doesn't work well on all websites. While it works great for Youtube and Twitch, it's useless for Osu! (osu.ppy.sh) since it just bugs and mutes page's sound until refresh if you try to increase or lower it, and for some other sites the sound just resets itself to the default volume every few seconds.

Pretty nice plugin, really helps, but sad there is no checkbox to remember configuration to use in any youtube tabs. tweaking every time is annoying if sound issue is more global than in one or two videos. Just wanna tweak once and forget it, but ... :<