Audio delay (lip sync error) breaks immersion immediately. It happens when the video processing takes longer than the audio decoding, or vice versa. Here is how to track down the source and sync them up.
Identify the Source
Play a video where you can see faces clearly (news or interviews are best).
- 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 (motion smoothing) is likely slowing down the picture, or the audio is arriving "too early."
The Fix Order
Try these steps in order to eliminate lag.
1. Change TV Audio Format to "Pass-through"
Most delays happen when the TV tries to process audio (e.g., 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.
2. Turn off "Game Mode" for Video Apps? NO.
Actually, turning ON Game Mode can sometimes help if the video is lagging behind the audio, as it removes video processing latency. However, usually, audio lags behind video. If video is late, turn OFF motion smoothing (TruMotion, Motionflow).
3. Adjust AV Sync Settings
Most TVs have a slider to deliberately delay audio.
- LG: AV Sync Adjustment. Toggle "Bypass" ON if available.
- Sony: A/V Sync. Set to Auto or On.
- Soundbars: Many soundbars (Sonos, Vizio) have a "Lip Sync" or "Audio Delay" feature in their specific mobile app or remote control.
4. Switch to Optical (The Diagnostic Test)
HDMI eARC involves complex "handshakes" that can introduce timing errors. To test, connect an Optical Cable (paid link) 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.
Brand-Specific Notes
- Sony: Known for eARC audio delays on older firmware. Update your TV. Set A/V Sync to "Auto".
- TCL: Go to Audio > Audio Delay. It has a manual slider (0-100ms).
- Apple TV: Run the Wireless Audio Sync calibration in Video and Audio settings (uses your iPhone mic to measure delay).
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