Fix IPTV Audio Video Out of Sync (Lip Sync)
When audio doesn't match the video (lips moving at wrong time), it's usually caused by buffer drift, audio passthrough delays, or processing latency. This is especially common with soundbars and AV receivers.
Common Symptoms
- ▸ Audio ahead of video - you hear words before lips move
- ▸ Audio behind video - you see lips move before hearing words
- ▸ Sync gets progressively worse during long viewing sessions
- ▸ Sync issues only when using soundbar or AV receiver
- ▸ Sync problems only on live TV, not VOD
Why This Happens
- ▸ Audio passthrough adding delay through soundbar/receiver
- ▸ Buffer drift during extended streaming sessions
- ▸ Bluetooth audio latency (headphones or speakers)
- ▸ TV motion smoothing/processing adding video delay
- ▸ Different processing speeds for audio vs video decoders
Quick Fixes
Try these solutions first - they resolve most issues.
Restart the streaming device and try again
Disable audio passthrough and use stereo/PCM output
Reduce buffer size in IPTV app settings
Disable TV motion smoothing (TruMotion, Motion Plus)
If using Bluetooth, switch to wired connection
Device-Specific Instructions
Note: Menu paths may vary slightly depending on your app version and device manufacturer.
Amazon Firestick
Lower buffer
In TiviMate: Settings > Player > Buffer size > Low or Medium. High buffer causes drift over time
Tip: Lower buffer = less drift but more buffering risk
Disable AV sync processing
Settings > Display & Sounds > Audio > AV Sync Tuning > Adjust slider until sync is correct
Tip: Firestick has built-in sync adjustment
Use HDMI direct
Connect Firestick directly to TV's HDMI instead of through soundbar. Use TV audio out for soundbar
Tip: Eliminates soundbar HDMI processing delay
Disable passthrough
Settings > Display & Sounds > Audio > Surround Sound > Stereo
Tip: Device processes audio instead of sending raw to TV
Restart regularly
Restart Firestick by holding Home button > Sleep, then unplug/replug power every few days
Tip: Prevents buffer drift accumulation
Android TV / Nvidia Shield
Adjust buffer
In your IPTV app, reduce buffer size to 1-2 seconds instead of default
Tip: Smaller buffer = less drift potential
Disable passthrough
Settings > Device Preferences > Sound > Digital Audio Out > PCM instead of Auto/Passthrough
Tip: Forces local audio processing
Use IPTV app sync
Many apps like Kodi have audio delay settings: Kodi > Settings > Player > Audio > Audio offset
Tip: Delays audio to match video
Check TV A/V sync
TV Settings > Sound > Expert > A/V Sync or Lip Sync adjustment
Tip: TVs often have their own sync settings
Clear cache and restart
Settings > Apps > [IPTV App] > Clear cache. Then restart the device
Tip: Removes accumulated buffer errors
Smart TV (Samsung/LG)
Disable motion smoothing
TV Settings > Picture > Expert Settings > Motion (TruMotion/Motion Plus/Clear Motion) > Off
Tip: Motion processing adds video delay
Game mode
TV Settings > Picture Mode > Game. This minimizes video processing delay
Tip: Reduces input lag but may affect picture quality
A/V sync setting
TV Settings > Sound > Expert Settings > Digital Output Audio Delay (or Lip Sync) > Adjust
Tip: Adds audio delay to match video processing
Change audio output
TV Settings > Sound > Sound Output > TV Speakers (instead of external audio)
Tip: Eliminates soundbar delay
Update firmware
Settings > Support > Software Update > Update Now
Tip: Firmware updates often fix A/V sync bugs
Pro Tips
- ★ Bluetooth headphones add 150-300ms of delay - use wired headphones for perfect sync
- ★ If sync only happens with soundbar, try optical audio out instead of HDMI ARC
- ★ Restart your device before watching movies/events to prevent session drift
- ★ Some soundbars have their own lip sync adjustment - check the soundbar settings too
When to Contact Your Provider
- ▶ Sync issues affect all users at the same time (stream is de-synced at source)
- ▶ Specific channels always out of sync from the start
Frequently Asked Questions
Why does sync get worse the longer I watch?
This is called buffer drift. Over time, small timing inaccuracies between audio and video buffering accumulate. Higher buffer settings make this worse. Solution: use lower buffer settings and restart the app every few hours for long viewing sessions.
Why does my soundbar cause lip sync issues?
Soundbars process audio which takes time (20-100ms). When audio goes through HDMI ARC to the soundbar, it's delayed while video displays immediately. Use your TV or soundbar's lip sync/audio delay setting to add delay to match, or connect the soundbar via optical for potentially less delay.