Skip to content
Stremio Setup Guide - Complete Tutorial & Documentation

Audio/Video Sync Issues

Audio/video sync issues (commonly called “lip sync” problems) occur when the audio and video tracks don’t play in perfect synchronization. This guide covers how to identify and fix these synchronization problems.

Understanding Sync Issues

What Causes Sync Problems

Common Causes:

  • Encoding Issues: Poorly encoded source files
  • Network Problems: Buffering causing delays
  • Device Performance: Hardware struggling to decode
  • Codec Mismatches: Audio/video codecs out of sync
  • Frame Rate Issues: Incorrect frame rate detection

Types of Sync Issues:

  • Audio Leads Video: Audio plays before video (most common)
  • Video Leads Audio: Video plays before audio
  • Intermittent Sync: Sync drifts over time
  • Complete Desync: Audio and video completely separated

Identifying the Problem

Steps

  1. Watch a Test Video

    • Play content with clear dialogue
    • Watch character’s mouth movements
    • Listen for timing of speech sounds

  2. Measure the Delay

    • Count milliseconds of delay
    • Use stopwatch or frame counting
    • Note if delay is consistent or variable

  3. Test Different Content

    • Try multiple videos from different sources
    • Check if issue is content-specific
    • Test with local files vs. streaming

Immediate Fixes

Built-in Sync Controls

Steps

  1. Access Audio Sync

    • During playback, right-click or press menu button
    • Look for “Audio Delay” or “Sync” options
    • Use keyboard shortcuts if available

  2. Adjust Audio Delay

    • Increase delay if audio leads video (+ values)
    • Decrease delay if video leads audio (- values)
    • Adjust in small increments (50-100ms)
    • Test and readjust as needed

  3. Keyboard Shortcuts

    • J Key: Decrease audio delay
    • K Key: Reset to default
    • L Key: Increase audio delay
    • Check player help for platform-specific shortcuts

Subtitle-Based Sync

Steps

  1. Use Subtitles as Reference

    • Enable subtitles for content
    • Watch timing between speech and subtitle appearance
    • Adjust audio delay to match subtitle timing

  2. Subtitle Delay Adjustment

    • If subtitles appear too early: increase audio delay
    • If subtitles appear too late: decrease audio delay
    • Fine-tune until speech matches subtitle timing
Tip

Subtitles are often perfectly synced, making them an excellent reference for audio timing adjustments.

Player Settings Adjustments

Video Player Configuration

Steps

  1. Access Player Settings

    • Click gear icon (⚙️) during playback
    • Navigate to Audio/Video settings
    • Look for sync and timing options

  2. Audio Settings

    • Audio Delay: Manual offset adjustment
    • Audio Buffer: Increase for stability
    • Sample Rate: Match source rate
    • Channels: Stereo vs. surround settings

  3. Video Settings

    • Frame Rate: Force specific FPS
    • Deinterlacing: For interlaced content
    • Aspect Ratio: Correct display ratio
    • Hardware Acceleration: Enable/disable GPU decoding

Advanced Player Options

Codec-Specific Settings:

  • H.264/AVC: Most compatible codec
  • H.265/HEVC: May cause sync issues on older devices
  • VP9: Web-optimized, usually good sync
  • AV1: Newest codec, potential compatibility issues

Buffer Settings:

  • Initial Buffer: Pre-load amount
  • Max Buffer: Maximum buffer size
  • Buffer Ahead: Look-ahead buffering
  • Network Timeout: Connection timeout settings

Source Quality Solutions

Content Source Issues

Streaming Quality:

  • Bitrate Mismatches: Audio/video encoded at different bitrates
  • Variable Quality: Adaptive streaming causing sync drift
  • Server Issues: Source server problems
  • CDN Problems: Content delivery network issues

Local File Issues:

  • Corrupt Files: Damaged video files
  • Improper Encoding: Poorly muxed audio/video
  • Container Format: MKV vs. MP4 vs. AVI issues
  • Codec Compatibility: Device can’t handle codecs

Quality Adjustments

Steps

  1. Lower Playback Quality

    • Switch to lower resolution (720p → 480p)
    • Reduce bitrate if option available
    • Disable high-quality audio
    • Test sync at different qualities

  2. Change Streaming Source

    • Try different add-on for same content
    • Switch to alternative stream quality
    • Use different server/location
    • Test with local file if available

Device-Specific Fixes

Android Devices

Steps

  1. Audio Settings

    • Settings → Sound → Audio Effects → Disable
    • Developer Options → Disable HW overlays
    • Audio → Sample rate → Match video

  2. Performance Mode

    • Enable “Performance Mode” if available
    • Disable battery optimization for Stremio
    • Force GPU rendering in developer options

  3. App-Specific

    • Clear Stremio cache
    • Update Android System WebView
    • Test with different video player

iOS Devices

Steps

  1. Audio Configuration

    • Settings → Stremio → Background App Refresh → Enable
    • Reset audio settings if needed
    • Check Bluetooth audio devices

  2. Performance Settings

    • Close background apps
    • Restart device
    • Update iOS to latest version

  3. Alternative Player

    • Try different video formats
    • Test with built-in player
    • Check codec support

Desktop Computers

Steps

  1. Audio Drivers

    • Update sound card drivers
    • Check sample rate settings
    • Test different audio devices
    • Disable audio enhancements

  2. GPU Settings

    • Update graphics drivers
    • Enable hardware acceleration
    • Check GPU control panel settings
    • Test different decoding methods

  3. System Settings

    • Disable exclusive mode audio
    • Check power management settings
    • Test with different browsers (web version)

TV/Stick Devices

Steps

  1. Display Settings

    • Match TV refresh rate to content
    • Check HDMI audio settings
    • Test different resolution outputs
    • Disable post-processing effects

  2. Device Optimization

    • Clear device cache
    • Close background apps
    • Update device firmware
    • Test wired vs. wireless connection

Network and Buffering Solutions

Network Optimization

Steps

  1. Stable Connection

    • Use wired Ethernet when possible
    • Ensure stable Wi-Fi signal
    • Test internet speed and stability
    • Avoid peak usage times

  2. Buffer Settings

    • Increase initial buffer size
    • Enable preload settings
    • Adjust network timeout values
    • Test with different buffer configurations

VPN Considerations

VPN Sync Issues:

  • Latency: VPN can add delay causing sync issues
  • Server Location: Distant servers increase latency
  • Protocol: Some VPN protocols add more delay
  • Kill Switch: Can interrupt streams

VPN Solutions:

  • Choose nearby VPN servers
  • Test without VPN to compare
  • Use split tunneling for local content
  • Switch VPN protocols

Advanced Troubleshooting

Codec Analysis

Steps

  1. Check File Properties

    • Use media info tools (MediaInfo, FFprobe)
    • Check audio/video codec details
    • Verify bitrate and sample rates
    • Look for encoding errors

  2. Codec Compatibility

    • Test with different codecs
    • Check device codec support
    • Update codec packs if needed
    • Try software decoding

Frame Rate Analysis

Frame Rate Issues:

  • Variable FPS: Content with changing frame rates
  • Incorrect Detection: Player misdetecting frame rate
  • Display Mismatch: Device display rate different from content
  • Telecine Content: 24fps content converted to 30fps

Frame Rate Fixes:

  • Force specific frame rate in player
  • Enable frame rate conversion
  • Match display refresh rate
  • Use frame interpolation if available

Third-Party Tools

Sync Correction Tools

External Tools:

  • VLC Media Player: Advanced sync controls
  • MPC-HC: Precise timing adjustments
  • PotPlayer: Multiple sync options
  • FFmpeg: Command-line sync correction

Audio Extraction Tools

Steps

  1. Extract Audio Track

    • Use tools like FFmpeg or MKVToolNix
    • Save audio as separate file
    • Analyze audio timing independently

  2. Remux with Sync

    • Correct timing in extracted audio
    • Remux with corrected audio
    • Test new file for sync

Prevention Strategies

Content Selection

Choose Better Sources:

  • Prefer high-quality, reputable add-ons
  • Check user reviews for sync issues
  • Test short clips before watching full content
  • Use verified, popular streaming sources

Device Maintenance

Regular Maintenance:

  • Keep device firmware updated
  • Update audio/video drivers
  • Clear cache regularly
  • Monitor device performance

Settings Optimization

Optimal Configuration:

  • Set appropriate buffer sizes
  • Enable hardware acceleration when possible
  • Use recommended quality settings
  • Configure audio settings properly

When to Accept Limitations

Unfixable Issues

Acceptable Limitations:

  • Very old or low-quality content
  • Live streams (always have some delay)
  • Experimental codecs on older devices
  • Network conditions beyond control

Alternative Solutions

Workarounds:

  • Use subtitles to follow dialogue
  • Adjust personal tolerance for minor sync
  • Switch to different content source
  • Accept as limitation of free streaming

Getting Help

Community Resources

Help Sources:

  • Stremio Forums: Sync-specific discussions
  • Reddit r/Stremio: User experiences
  • Video Player Forums: VLC, MPC-HC communities
  • Codec Forums: FFmpeg and codec discussions

Professional Help

When to Seek Help:

  • Sync issues on all content
  • Hardware-specific problems
  • Issues after system updates
  • Problems affecting multiple devices

Best Practices

✅ Do:

  • Test sync on short clips first
  • Use built-in player controls for adjustments
  • Check network stability
  • Update device drivers regularly
  • Try different content sources
  • Use subtitles as timing reference
  • Keep devices and apps updated

❌ Don’t:

  • Ignore minor sync issues that can be fixed
  • Use very old or outdated devices
  • Expect perfect sync on low-quality streams
  • Skip testing different player settings
  • Use unstable internet connections
  • Disable hardware acceleration unnecessarily
  • Use cracked or modified video players

Sources: