Before touching any setting, work out which way round it is. Almost every audio delay slider on a TV or soundbar does one thing: it holds the sound back. So if the sound arrives after the lips move, a slider fixes it in about a minute. If the sound arrives before the lips move, that same slider is useless, and the problem is the picture taking too long — a completely different job.
The exception is worth knowing if you own one: a few AV processors can pull audio forward by buffering the video instead. The NVIDIA Shield is often cited here, but its audio/video sync slider only delays audio — it cannot pull it forward. A few AV processors do expose negative offsets. If you have one of those in the chain, it's the piece that can fix early audio.
(There is one exception, and it's automatic rather than something you set: on a working eARC link the TV itself can delay the video. More on that below.)
Mute the TV and watch a news anchor. Speech is the easiest thing to judge.
If the sound is late
Push the audio later, on whichever device is producing it.
- LG — Settings > All Settings > Sound > Additional Settings > AV Sync Adjustment
- Samsung — Settings > Sound > Expert Settings > Digital Output Audio Delay
- Sony — Settings > Display & Sound > Audio output > A/V Sync
- TCL / Hisense (Google TV) — Settings > Display & Sound > Sound > Advanced Settings > Lip Sync
- Vizio — Menu > Audio > Lip Sync
- Soundbars — Audio Delay, Audio Sync or TV Dialog Sync, in the bar's app or on its remote
The sliders usually run 0–300 ms. Start small and work up rather than jumping to the middle — but don't assume a large number means something is broken. A simple PCM chain usually needs only tens of milliseconds. A bitstreamed Dolby Digital or Atmos chain has to decode before it can play, and measured latencies in that range routinely land between roughly 80 and 200 ms. Manufacturer defaults are not published in any consistent place, so treat a three-figure value as normal rather than broken. If your correct value is 120 ms on an Atmos soundbar, that's the decoder, not a fault.
Adjust on the device playing the sound. If that's a soundbar, adjust the soundbar, not the TV — the bar is where the extra processing happens.
If the sound is early
No audio slider will help. The video is arriving late, and you have to make the picture faster.
Turn off motion smoothing and noise reduction on the input the source is plugged into. Game Mode is the one that matters here — it's the only picture mode that actually bypasses the processing pipeline, and it's typically worth 50–100 ms of video latency on its own. On many sets that alone brings the two back together.
Filmmaker Mode is not a substitute. It switches off motion smoothing, sharpening and overscan, which is good for how the picture looks, but it isn't a low-latency mode and it doesn't cut the pipeline delay the way Game Mode does. If you're chasing early audio, use Game Mode and accept the flatter picture while you diagnose.
Motion interpolation is the worst single offender, because it buffers frames to invent new ones, and that buffer is picture latency you can't compensate for downstream.
eARC is supposed to do this for you
This is the part most people don't know. HDMI has carried automatic lip-sync correction since HDMI 1.3 in 2006 — devices report their audio and video latency over EDID, and the receiver delays audio to match. eARC extends it: the audio device tells the TV how long its processing takes, and the TV delays the video accordingly.
So on a working eARC chain you shouldn't need the slider at all. When you do, that's information: the automatic negotiation isn't happening. It fails most often in mixed-brand systems, where the reported latency figures are wrong or absent, and on plain ARC rather than eARC.
Before you dial in a manual offset, check eARC is actually enabled on both ends rather than the link having quietly fallen back to ARC. A manual offset on top of working auto-correction over-corrects and makes things worse.
Apple TV and other streaming boxes
An external streamer adds a third device to the chain, and one Apple TV setting causes more sync complaints than any slider.
Turn on Settings > Video and Audio > Match Content > Match Frame Rate. Film is 24fps, and with this off the Apple TV outputs it at about 59.94Hz using 3:2 pulldown. That produces judder — uneven motion on pans — rather than audio drift as such, but it also means the box is switching cadence behind the scenes, and each switch is a chance for the chain to settle on a different offset.
Worth being straight about the trade-off: turning Match Frame Rate on is also reported to introduce sync problems on some chains, because every format change renegotiates the link. If your sync is stable and only the motion bothers you, this is the fix. If your sync is the problem, try it both ways rather than assuming on is correct.
Leave Audio Format on its default too. Forcing a format triggers extra handshakes, and each one can land the chain on a different offset.
If sync is fine on the TV's own apps but wrong through the Apple TV, the box is the variable and these two settings are where to look.
If it drifts instead of sitting at a fixed offset
A fixed offset is a processing-latency problem. Drift is a handshake problem, and they don't share a fix.
Decoding latency is higher for Atmos and DTS than for PCM, so if sync only goes wrong on surround content, set the TV's digital audio output to PCM as a test. If PCM is stable and Atmos isn't, the decoder is the source of the delay and the soundbar's own sync setting is the place to correct it.
If it drifts on everything, suspect the link. A marginal cable renegotiates mid-stream and each renegotiation can land on a different offset — swap in a certified Ultra High Speed cable on the eARC hop. Optical is the fallback that ends drift for good, because it never renegotiates. The trade-off is real: optical cannot carry Atmos or DTS:X, only Dolby Digital 5.1 or stereo. Stable 5.1 beats intermittent Atmos for most people, but it is your call.
Power-cycling the chain — everything unplugged 30 seconds, audio device powered first — clears a one-off bad handshake. If it comes back within a day, it wasn't a one-off.
See also
FAQ
Sound is behind the picture. Use the audio device's delay slider. Work up from small values rather than starting in the middle — but on an Atmos or DTS chain the right answer is often over 100 ms, and that's the decoder, not a fault.
Sound is ahead of the picture. No TV or soundbar slider fixes this. Turn off motion smoothing and switch that input to Game Mode specifically — Filmmaker Mode tidies the picture but doesn't cut the latency. The picture is what's late.
Why do I need this at all on eARC? You shouldn't. HDMI has done automatic lip-sync correction since 2006 and eARC extends it to delaying video. Needing a manual offset means the negotiation isn't working, usually in a mixed-brand chain or on a link that fell back to ARC.
It only drifts on Atmos. Surround decoding costs more latency than PCM. Set the digital output to PCM to confirm, then correct it on the soundbar rather than the TV.
Does Apple TV's Match Frame Rate matter? It fixes judder on 24fps film, which is a motion problem rather than a sync one. It can help sync and it can also disturb it, since every format switch renegotiates the link — try it both ways rather than assuming on is right.