Works really well!

Sound Fixer is one of the best and most reliable extensions I've ever found for sound problems on Facebook, and YouTube. I've been using it for about 10 months, and it has not let me down. 👍👍

It suddenly stopped working without a warning or anything

Youtube playback speed control does not work if this plugin is installed.

Rewelacja do cichych nagrań! Brawo!

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

Youtube playback speed control does not work if this plugin is installed, so it is completely unsuitable to me.

Works great misses importent core features. I'm still missing a tool that let me adjust the audio by frames, fyi Marques Brownlee did an experiment uploading and downloading the same youtube video 100 times and with every upload the audio will shift 4 frames. And one thing that annoyed me today, was that a video had switched stereo channels, would be great to have a checkbox aside Mono that says switch right and left channel. Then this tool will be a five star add-on for me.