When dialogue arrives before an actor’s lips move — or a moment afterwards — even a good home cinema system becomes distracting. Here’s how to find the cause without changing every setting at once.
The lip-sync slider looks like the obvious fix, but it only helps when the sound arrives too early. If dialogue is already late, adding more audio delay makes it worse.
The fault might be in the programme, a streaming app, the television, an HDMI-connected box or the soundbar itself. Work out which part of the chain is responsible before sacrificing surround sound or gaming features to hide it.
Is the sound ahead of the picture, or behind it?
Start with a familiar scene containing clear speech. A close-up of someone talking is useful; a sharp on-screen impact, such as a handclap, is even easier to judge. Replay the same moment after each change. Dubbed programmes can have imperfect mouth movements to begin with, so choose an original-language scene if possible.
Sound is early: You hear a word or impact before the corresponding movement. A control that adds audio delay may bring it back into line. Start from the existing setting and make small adjustments rather than jumping straight to the maximum.
Sound is late: You see the mouth or impact move before you hear it. A conventional audio-delay slider cannot fix this; it can only postpone the sound further. First reduce any delay you previously added, then look for unnecessary processing or a better audio route.
Some televisions and AV receivers have automatic lip-sync functions that can also adjust video timing. That is different from a simple manual audio-delay slider. The label alone does not tell you what a setting can do, so check the manual for your particular model. Sonos makes the same early-versus-late distinction in its TV audio-sync guidance.
Why lip-sync delay happens
The picture and soundtrack do not necessarily travel through your equipment at the same speed. A TV may scale an image, handle HDR and apply motion processing while a separate soundbar decodes Dolby audio, processes dialogue or creates a virtual surround effect.
The signal path matters, too. A games console might send video directly to the television, while the television forwards the sound through HDMI eARC to an AV receiver. Those devices have to keep their separate processes aligned. Automatic compensation helps on compatible hardware, but it does not guarantee identical results from every app, source and format.
A delay that changes when you switch from a built-in app to a console is a useful clue. It suggests that the difference lies in the source, connection or processing path, rather than a fixed problem with the speakers.
Fix TV and soundbar lip-sync problems in the right order
1. Compare the TV speakers with the soundbar
Play a short scene through the television’s own speakers, then select the soundbar or AV receiver and play it again. Keep the programme, scene and picture settings the same. Do not run both speaker systems together; the echo can confuse the comparison.
If the television speakers match the picture but the soundbar does not, concentrate on the TV’s external audio output, the cable connection, sound format and soundbar processing. If both are out of sync, the source material or television is a stronger suspect. This is a diagnostic clue, not a guarantee: televisions can process their internal and external speakers differently.
2. Try a built-in app and an HDMI device
Check a TV app such as Netflix or BBC iPlayer, followed by an HDMI-connected streaming box, Blu-ray player or console. If only the external device has the problem, inspect that input and its audio settings. If only one app or one programme is affected, try another title before changing the system.
Live television can occasionally arrive with its audio already misaligned. If the issue is confined to one channel, the broadcaster or set-top box provider may need to correct it; LG’s TV audio-sync advice makes that distinction.
3. Restart the affected equipment and check its connections
Turn off the relevant devices and restart them. Reseat the HDMI leads and confirm that the soundbar is connected to the television’s HDMI socket marked ARC or eARC, if that is your intended connection. Check the selected sound output in the TV menu.
A poor connection commonly causes dropouts or handshake problems rather than a neat, constant lip-sync offset, but ruling it out is quick. If optical and HDMI cables both run to the sound system, make sure you know which connection is actually carrying the sound; do not swap paths blindly.
4. Remove one processing step
If audio is late, temporarily disable one optional sound-processing feature, such as a virtual surround mode, an audio enhancement or additional dialogue processing. Replay your test clip. If it makes no difference, restore the original setting before trying another.
Picture processing matters as well. Motion smoothing can delay the image, while Game Mode normally cuts video processing to improve responsiveness. Switching picture modes can therefore change the relationship between picture and sound. Keep a note of which mode you used and remember that the setting giving the closest lip-sync is not automatically the best choice for gaming.
5. Compare Dolby audio with stereo PCM
If the mismatch appears only with Dolby surround sound, briefly change the relevant TV or source output to stereo PCM. If the timing improves, that suggests the previous format or a decoding/conversion stage was adding latency.
It is a test, not a recommendation to leave an expensive Dolby Atmos system in stereo. Restore your preferred format afterwards and investigate which device was doing the extra work. Sony likewise recommends PCM as one of several model-dependent soundbar checks.
6. Adjust delay only after narrowing down the fault
If sound is early and the connection is stable, use the TV, soundbar or AV receiver’s manual lip-sync control. Change it in small steps and replay exactly the same scene. If one input needs a different adjustment from another, look for a per-input setting rather than applying a single value to everything.
If sound is late, do not keep increasing audio delay. Return to steps four and five, or test a different signal path.
HDMI ARC, eARC and optical: which is better for sync?
HDMI ARC lets a television return audio to a soundbar or AV receiver through an HDMI cable. eARC offers much greater audio bandwidth and improved capabilities for compatible equipment, including high-bitrate surround formats. Our HDMI eARC explainer covers the format and connection differences in more detail.
eARC can avoid some unnecessary conversion, but it does not make lip-sync problems impossible. A correctly configured ARC setup can stay perfectly aligned, while an eARC setup can still suffer from a slow audio processor or source-specific fault.
Optical is a sensible alternative for supported stereo or compressed surround formats and can be useful as a comparison. It lacks the HDMI ARC/eARC feature set and does not carry every high-bandwidth format. Changing to optical solely because an HDMI connection has a sync problem may create new limitations without curing the original cause.
Pass-through, PCM and Dolby formats explained
Television menus often offer Auto, Pass Through and PCM, with the precise names varying by manufacturer.
Pass Through generally asks the TV to send a compatible incoming audio format onwards rather than convert it first. That may reduce processing, provided the TV and sound system both support the format. It is not a promise that every HDMI input or streaming app can pass every soundtrack unchanged.
PCM is decoded digital sound, not automatically a lower-quality option. Multichannel PCM can be an excellent way to carry surround audio over a compatible eARC connection. However, some televisions and older ARC or optical paths output only stereo PCM. Check what your particular equipment supports before making PCM your permanent setting.
Dolby Digital and Dolby Digital Plus are compressed formats. Dolby TrueHD is a lossless format often used on Blu-ray discs. Dolby Atmos adds height and object-based sound information and can be delivered through different underlying formats. Streaming services commonly use Dolby Digital Plus for Atmos, whereas certain Blu-ray or console output arrangements need eARC or direct HDMI to a suitable receiver.
If changing from a Dolby format to stereo removes the delay, do not conclude that Dolby Atmos itself is faulty. The culprit might be a TV converting a format, an unsupported pass-through setting or processing elsewhere in the chain.
Should you connect a console or streaming box to the TV or soundbar?
Two arrangements are common: source → TV → soundbar through ARC/eARC, and source → soundbar or AV receiver → TV.
The first makes sense when the television supports all the picture features of an Xbox Series X, PS5 or streaming device and passes the required audio to the sound system. The second can help when the TV is responsible for delayed audio, because the receiver or soundbar handles the source sound directly. Sony includes a direct-to-soundbar connection among its HDMI troubleshooting options.
Before moving a console, check the audio system’s HDMI video pass-through specification. Not every soundbar with an HDMI input can pass 4K at 120Hz, variable refresh rate, HDR and automatic low-latency mode. Fixing a fraction of a second of audio delay is little consolation if you lose the gaming features you paid for. If the bar cannot pass them, leave the console connected to the TV and investigate eARC output instead.
An AV receiver may have its own source-by-source lip-sync setting. Check whether it is adding delay before applying a second adjustment at the television.
Bluetooth audio: why wireless can be more noticeable
Bluetooth introduces encoding, transmission, buffering and decoding between the TV and headphones or speakers. The delay depends on both devices and their supported codecs. A product advertised as low latency cannot deliver that benefit if the other device does not support the same mode.
If TV speakers and a wired soundbar are in sync but Bluetooth headphones are late, the wireless connection is the obvious place to investigate. Try a supported wired audio route when possible, or look for a Bluetooth-specific sync adjustment. Sony notes that Bluetooth compensation can affect responsiveness in games and that some picture modes handle AV sync differently. Its AV-sync help guide explains the trade-off.
A dedicated soundbar’s wireless rear speakers should not be confused with an ordinary Bluetooth link from TV to soundbar. The sound system usually coordinates its own rear channels, so troubleshoot it as one system unless its manual says otherwise.
Apple TV 4K, streaming apps and other external boxes
Apple TV 4K can select an appropriate supported audio format automatically. It is normally better to leave that behaviour in place while diagnosing lip-sync, rather than immediately forcing Dolby Digital 5.1 or stereo. Apple’s audio-format support page explains what the alternatives change.
The Wireless Audio Sync option uses an iPhone to calibrate playback between wired and wireless speakers. It is useful in the circumstances Apple describes, but it is not a universal HDMI soundbar repair button. Follow Apple’s calibration instructions only if they match your arrangement.
Built-in TV apps remove an external HDMI source from the equation, though they still use the television’s audio processing. If one app runs late while another is fine, check that app and the specific programme. If an Apple TV or Fire TV alone is affected, examine its HDMI input and audio output rather than changing every TV-wide setting. Our comparison of Apple TV 4K and built-in smart TV apps explains the wider reasons for choosing each route.
When the problem refuses to go away
Write down what you have established: the affected source or app, whether sound is early or late, whether TV speakers behave differently, the connection type and the audio format. Include the model numbers and software versions of your TV and sound system.
Check for device firmware and app updates. A factory reset should be a last resort, once you have recorded your settings and tried the manufacturer’s model-specific guidance. A fault across several sources may need support or repair; a fault tied to one broadcast or video file should be reported to its provider instead.
Tech Torque Verdict
Most lip-sync problems are easier to solve once you stop treating every delay as the same fault. Work out which arrives first, compare the TV speakers with the soundbar, then isolate the app or input. Make one change at a time so you know which adjustment actually helped.
Add audio delay only when the sound is early. When it is already behind the picture, look instead at processing, audio formats and connection paths. HDMI eARC is useful, but it is not an automatic cure, and leaving a surround system in stereo should be a diagnostic compromise rather than the first permanent fix.
