Audio delay (lip sync error) breaks immersion immediately when watching TV or movies. This happens when video processing takes longer than audio decoding, or vice versa, creating a mismatch between what you see and hear.
Quick answer
• Change TV audio format to "Pass-through" to stop audio processing delays • Turn off motion smoothing (TruMotion, Motionflow) if video lags behind audio • Use AV Sync settings to manually adjust timing with built-in TV controls • Test with optical cable to bypass HDMI eARC timing issues
Symptoms
• Voices don't match lip movements when people speak on screen • Audio arrives noticeably before or after the video action • Problem affects all content or only specific inputs/apps • Delay is consistent across different shows and movies
Quick checks
Play a video where you can see faces clearly (news or interviews work best) and test these scenarios:
• TV Native Apps (Netflix, YouTube): If these lag, the delay is in your TV's audio processing or the ARC/eARC link • External Device (Cable Box, PS5): If native apps are fine but HDMI inputs lag, the TV's video processing is likely slowing down the picture
Step-by-step fix
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Change TV audio format to "Pass-through" Most delays happen when the TV tries to process audio (converting Dolby Digital to PCM): • LG: Sound → Advanced → Digital Sound Output → Pass Through • Sony: Sound → Audio Output → Pass through mode → Auto • Samsung: Sound → Expert Settings → Digital Output Audio Format → Pass-Through
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Turn off motion smoothing if video lags behind audio Disable motion smoothing (TruMotion, Motionflow) in your TV's picture settings. Turning ON Game Mode can also help by removing video processing latency.
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Adjust AV Sync settings Most TVs have a slider to deliberately delay audio: • LG: Find AV Sync Adjustment and toggle "Bypass" ON if available • Sony: Set A/V Sync to Auto or On • TCL: Go to Audio → Audio Delay and use the manual slider (0-100ms) • Soundbars: Check your soundbar's mobile app or remote for "Lip Sync" or "Audio Delay" features
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Test with optical cable Connect an optical cable from TV to soundbar. Optical is a "dumb" stream with very low latency. If optical fixes it, the issue is your HDMI CEC/eARC negotiation.
If it still isn't working
• Update your TV firmware — Sony TVs especially have known eARC audio delays on older firmware • Try different HDMI cables — use high-quality 8K-rated HDMI cables for eARC connections • Apple TV users: Run the Wireless Audio Sync calibration in Video and Audio settings (uses your iPhone mic to measure delay) • Reset audio settings to factory defaults and reconfigure from scratch
FAQ
Why does the delay only happen with certain apps? Native TV apps use different audio processing than HDMI inputs. External devices may have additional video processing that creates timing mismatches.
Should I use Game Mode to fix audio delay? Only if video is lagging behind audio. Game Mode removes video processing latency but usually audio lags behind video, not the other way around.
Is optical better than HDMI eARC for audio? Optical has lower latency but supports fewer audio formats. It's useful for testing but HDMI eARC provides better audio quality when working properly.
Can a bad HDMI cable cause lip sync issues? Yes, poor-quality HDMI cables can cause timing issues with eARC connections. Use certified high-speed HDMI cables for best results.
Related fixes
Quick Fix Accessories
• Test Cable: Amazon Basics Optical Cable (paid link) • Proper HDMI: Zeskit Maya 8K HDMI (paid link) • Full list: Quick Fix Accessories Hub