Works fine, but UI isn't comfy for me, hope to see:
1) area/button to set the input range slider to default position (for e.g. by click on %Name or %Value).
2) markings with 25% 50% 75% (e.g. datalist with option)
3) hide unwanted stuff (e.g. 3D Audio) by options or collapse element (e.g. div display:none/block with :checked)
4) set step to 1 or 5 instead of 0.01 (for input type="range", since 100-10000 values is too precise and redundant). Clicking on min/max number move slider with 5 steps (e.g by 20% when 100%)

Thanks for extension!

Most of the times works fine (sometimes it has no effect in the audio), I only use it to amplify volume in youtube.

The only thing that keeps this from being 5 star is that it causes playback speed, which I usually set at 1.25 or higher, to default to 1. Other than that it's the best I've found for listening to too low volume youtube broadcasts and the only one I've found that works well with hoopla.

Cool addon, but please make default volume 100, not 10. Every time i want amplify sound i have to set volume back to 100, its annoying.

It works according the description. The problem I found is that I couldn´t save the settings I chose and apply them in every webpage; because of that, every time I opened a new tab or reload the same page I had to configure again the extension.