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Preview of LagSync - Bluetooth Audio Fix

LagSync - Bluetooth Audio Fix by Simon

Fix audio and video delay caused by Bluetooth latency. Sync your sound perfectly on YouTube, Netflix, and HTML5 video to get perfect lip-sync.

3.8 (6 reviews)
154 Users
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Stop Watching Bad Dubs. Start Watching LagSync. Bluetooth headphones shouldn't mean out-of-sync video. LagSync perfectly aligns your audio and video on YouTube, Netflix, and Twitch with a single click.Optimized for Your Hardware. Whether you're using high-end noise-canceling headphones or budget earbuds, get the perfect delay setting instantly. Switch between aptX, AAC, and SBC modes to match your device's specific latency.Lightweight, Secure, and Ad-Free. Fix your A/V sync without the bloat. LagSync is a clean, privacy-focused extension that offers professional delay correction without tracking your history or showing intrusive ads.The Ultimate Sync Fix for Every Stream. Tired of audio that doesn't match the action? LagSync provides a universal solution for Bluetooth delay across the web. Whether you're on YouTube, Netflix, Twitch, or Prime Video, enjoy perfectly synchronized playback with a single click.
About this extension
Fix Bluetooth audio delay on YouTube, Netflix, and more. Adjust sync in real-time for perfect lip-sync with your headphones.

STOP THE LIP-SYNC FRUSTRATION

Bluetooth headphones often suffer from noticeable latency, causing the audio to fall out of sync with the video. LagSync is a technical tool designed to fix this by letting you adjust the audio or video offset in real-time.

While optimized for YouTube and Netflix, LagSync is built to work on almost all standard HTML5 video players to ensure a perfectly synchronized viewing experience.

MAIN FEATURES
  • Real-time Sync: Shift the audio offset instantly without refreshing the page or re-buffering.
  • Broad Compatibility: Specialized hooks for major streaming platforms and universal support for HTML5 video.
  • Precision Control: Fine-tune the delay in milliseconds (ms) for exact synchronization.
  • Performance Focused: Minimal code footprint that won't slow down your tabs or drain your battery.

HOW IT WORKS
  1. Open a video in your Firefox browser.
  2. Click the LagSync icon in your toolbar.
  3. Adjust the slider or input a specific millisecond value until the sync is perfect.

PRIVACY FIRST

Firefox users value their data, and so do we.
  • Zero Tracking: We do not collect, store, or transmit your browsing history or video data.
  • Local Storage: All your settings and offsets stay locally in your browser.
  • No Ads: LagSync is a utility tool, not an ad-delivery platform.

SUPPORT THE PROJECT

LagSync is a passion project. If it saved your movie night, consider supporting the development here:
Support LagSync

WHY LAGSYNC?

Most web players lack built-in tools for audio delay compensation. LagSync provides a straightforward, manual solution for users who want their media to match their audio perfectly—no matter what headphones they are using.
Rated 3.8 by 6 reviewers

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Permissions and data

Required permissions:

  • Access your data for sites in the youtube.com domain
  • Access your data for sites in the youtube-nocookie.com domain
  • Access your data for sites in the youtu.be domain
  • Access your data for sites in the netflix.com domain
  • Access your data for sites in the twitch.tv domain
  • Access your data for sites in the vimeo.com domain
  • Access your data for sites in the disneyplus.com domain
  • Access your data for sites in the primevideo.com domain
  • Access your data for sites in the amazon.com domain
  • Access your data for sites in the hulu.com domain
  • Access your data for sites in the max.com domain
  • Access your data for sites in the hbomax.com domain
  • Access your data for sites in the peacocktv.com domain
  • Access your data for sites in the paramountplus.com domain
  • Access your data for sites in the tv.apple.com domain
  • Access your data for sites in the crunchyroll.com domain
  • Access your data for sites in the dailymotion.com domain
  • Access your data for sites in the plex.tv domain
  • Access your data for sites in the kick.com domain

Optional permissions:

  • Access your data for sites in the youtube.com domain
  • Access your data for sites in the youtube-nocookie.com domain
  • Access your data for sites in the youtu.be domain
  • Access your data for sites in the netflix.com domain
  • Access your data for sites in the twitch.tv domain
  • Access your data for sites in the vimeo.com domain
  • Access your data for sites in the disneyplus.com domain
  • Access your data for sites in the primevideo.com domain
  • Access your data for sites in the amazon.com domain
  • Access your data for sites in the hulu.com domain
  • Access your data for sites in the max.com domain
  • Access your data for sites in the hbomax.com domain
  • Access your data for sites in the peacocktv.com domain
  • Access your data for sites in the paramountplus.com domain
  • Access your data for sites in the tv.apple.com domain
  • Access your data for sites in the crunchyroll.com domain
  • Access your data for sites in the dailymotion.com domain
  • Access your data for sites in the plex.tv domain
  • Access your data for sites in the kick.com domain

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Version
1.4.1
Size
123.1 KB
Last updated
9 days ago (Aug 17, 2026)
License
All Rights Reserved
Version History
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