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Preview of Numex Volume Boost

Numex Volume Boost by Knackered

Make any video or audio up to 6× louder with built-in anti-clipping.

5 (2 reviews)5 (2 reviews)
8 Users8 Users
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About this extension
Numex Volume Boost makes every video and audio player louder and clearer.
Perfect for movies, music, podcasts, or quiet videos on YouTube, Twitch, and more.

Features:
• Boost volume up to 6× using the WebAudio API
• Anti-clipping option to reduce distortion at high gain
• Works on all HTML5 audio and video elements
• Simple, lightweight, no data collection

Limitations:
• DRM-protected players (e.g. Netflix, Prime Video) may not be supported
• Some embedded iframes may not allow audio routing
Rated 5 by 2 reviewers
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Permissions and dataLearn more

Required permissions:

  • Access browser tabs
  • Access your data for all websites
More information
Add-on Links
  • Support site
Version
3.1.0
Size
23.04 KB
Last updated
5 days ago (Sep 6, 2025)
Related Categories
  • Photos, Music & Videos
License
MIT License
Version History
  • See all versions
Tags
  • music
  • youtube
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Release notes for 3.1.0
🚀 Numex Volume Boost 3.1.0 – Netflix Update & Stability Boost
✨ What’s New

🔄 Smart Re-hooking – automatically reconnects to new <video> elements that Netflix frequently recreates.
🛡️ DRM Notice – when WebAudio is blocked by DRM, a short, non-intrusive banner explains what’s happening instead of leaving users confused.
🎛️ Autoplay Unlock – ensures the AudioContext resumes on the first click or key press, even on sites with strict autoplay policies.
🌐 Deep Shadow DOM Scan – improved detection of embedded players inside iframes and shadow roots.
🪄 Minor fixes to overlay initialization and badge counter updates.

🎹 Hotkeys (unchanged)

Alt+Shift+↑ – increase volume (+10%)
Alt+Shift+↓ – decrease volume (–10%)
Alt+Shift+M – mute/unmute
Alt+Shift+O – toggle floating controller
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