doesn't work at all

doesn't work with audius.co

Some of sites can't play video

Does nothing.

It breaks some websites and video players

The plugin works very well at what its supposed to do, but unfortunately it has a major side affect.
It prevents video thumbnails from previewing videos across all sites and even prevents videos from playing on some sites.
So even though its a good equalizer its unusable because of its major side affect.

Add-on brake video playback like streamable and can't load messenger properly, after uninstall everything start working normally

Interferes with video playback speed on any video (youtube/twitch/etc.)

This add-on breaks playback speed settings on youtube.

This break many things, including YouTube playback speed, Google Drive audio playback, Google "define" feature's audio (when I look up a word using by searching "define", it provides a clip of that word's pronunciation, which can't be played with this add on)

I can't get it to work with Spotify on a PC. I'm looking into it. Probably me.

Didn't do anything. Did not work with Firefox 77.0.1

No perceptible difference in audio volume no matter what you do

No perceptible effect. Ubuntu Fossa Firefox 76.9 Canonical 1.0

stops streaming tv when activated!

This, straight up, does not work. I opened Spotify and turned on some music and there is no difference. I even tried refreshing, saving presets, using built in presets, etc. Just doesn't do anything at all.
I have been trying to find a good equalizer for my mac. Sadly, they either don't work or are expensive for how simple an equalizer software is. It really should be built into the OS, especially considering that Apple created the iPod and how connected they are to the music industry.

Doesn't work with Napster (streaming service) out of the box, unfortunately. Although neither does "Audio Equalizer and Amplifier," so maybe it's just Firefox not playing nice with my system.

Dose not work.
Each slider can move but sound is not changing at all.
Other Equalizing addons for Firefox dose also not work.
But same addons can work in chrome.