I've only noticed this asynchrony in recent years and it's getting worse.
It happens when I watch sports/movies/shows/news: everything.
I'm certain I'm not the only person to have noticed this: I'd be very surprised if a lot of — if not most — people have the same problem.
I asked Perplexity Pro for an explanation: it follows.
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Lip‑sync problems are almost always timing mismatches somewhere in the chain: the video and audio are being processed, transmitted, or decoded on slightly different schedules, and your eyes can easily see a delay of even 40–80 ms.[tcl +1]
Below is what’s actually going on and why you’re seeing it so widely across sports, movies, TV, and on different devices.
Core technical causes
Modern TV, streaming, and mobile playback is a pile‑up of separate digital processes: encoding, transmission, decoding, image processing, and audio processing.[fpdvision +1]
Common low‑level causes:
• Video processing is slow, audio is fast: TVs do heavy work on video (upscaling, motion smoothing, noise reduction, HDR tone‑mapping), which adds extra milliseconds of delay, while the audio often goes through a simpler path and arrives earlier.[tcl +1]
• Or audio processing is slow: Soundbars/receivers may spend extra time decoding Dolby Digital/Atmos, applying room correction, or virtual surround, so sound comes late relative to the picture.[sony +1]
• Different paths for audio vs video: Example: Apple TV → HDMI into TV (video), with audio sent via HDMI‑ARC/eARC to a soundbar; each hop can add its own delay and they rarely match by default.[whizz-experts +2]
Even when everything “works,” those few tens of milliseconds difference are enough to make speech look off, especially on sports where you see lips and impact sounds (bat hitting ball, ball hitting rim) very clearly.[fpdvision +1]
Source/broadcast side problems
Sometimes the desync is already baked into the feed before it ever reaches your devices.[tablotv +1]
• Broadcast or stream encoding errors: A TV channel, live sports stream, or DVR/streaming back‑end can have corrupted frames or misaligned audio/video timestamps, which pushes audio ahead or behind video. This is documented with certain OTA DVR streams where bad signal corrupts the multiplex and blows A/V sync.[tablotv]
• Ad insertion and stitching: On some streaming services, the transition into or out of ads briefly throws timestamps off so the program resumes out of sync until you pause/rewind or restart the stream.[facebook]
• Platform‑specific bugs: Firmware bugs in streaming boxes, TVs, or apps routinely cause accumulating delay until you restart the app/device.[youtube +1]
Because you’re seeing it across “sports/movies/TV/news” and across devices, at least some of what you’re noticing will be upstream issues you can’t fully fix client‑side.[sony +1]
Device and connection factors
Different device/connection choices create different timing behaviors even with the same content.
TV + soundbar/receiver
When a TV sends video to its own panel and audio out over HDMI‑ARC/eARC or optical, paths can get out of sync.[fpdvision +1]
Typical contributors:
• ARC/eARC handshake and buffering: The TV buffers audio to send over ARC/eARC; the soundbar then decodes and applies processing, which can add 50–150 ms.[whizz-experts +2]
• Audio output mode (Bitstream vs PCM): Bitstream means the TV passes compressed surround formats to the soundbar to decode, which is slower and more error‑prone; switching to PCM often reduces delay because decoding happens once and earlier in the chain.[reddit +1]
• “Enhancement” modes: Virtual surround, dialogue enhancement, night mode, or room correction can all increase processing time.[sony +1]
Many TVs and soundbars add a manual Audio/Lip Sync/AV Sync setting so you can delay audio to match the picture, but this only really helps when sound is ahead of video; if the video is behind, those controls can make things worse.[arylic +1]
Streaming boxes and apps (including Apple TV)
Streaming devices have to match the framerate and dynamic range of content to what the TV expects, and that negotiation can affect timing.
• Frame‑rate conversion: If a box is outputting everything at, say, 60 Hz while content is 24/30/50 Hz, it has to insert or drop frames; some platforms handle this badly and drift out of sync over time.[whizz-experts +1]
• Audio format negotiation: Apple TV, Fire TV, etc. decide whether to send Atmos, Dolby Digital 5.1, or PCM; mismatches between what the box sends and what the TV/soundbar expects can introduce audio lag, especially over ARC.[sony +1]
• Wireless audio calibration: Newer Apple TV models rely on an iPhone‑based Wireless Audio Sync calibration to compensate for total chain delay to a TV or receiver; if that calibration is off or never run, you may see systemic lip‑sync error.[youtube +1]
Phones and tablets
On iPhone/iPad/Android, the same principles apply, but the bottlenecks move around.[google]
• Software decoding load: Heavy decoding (high bitrate streams, HDR, 4K on some devices) can cause the system to slightly lag either video or audio pipeline.
• Third‑party apps and overlays: On phones, additional processing layers (e.g., audio effects, screen recorders, or buggy video players) can throw the streams out of sync; safe‑mode tests are often recommended to isolate app‑level interference.[google]
Because mobile SoCs are doing everything in one integrated system, they will often maintain sync a bit better than a TV plus external audio gear—but they’re still not immune.
Wireless audio (Bluetooth, AirPods, etc.)
Any time the audio leaves the device wirelessly, additional encoding, buffering, and retransmission adds delay.[arylic +1]
• Bluetooth codec latency: Standard SBC/AAC Bluetooth adds tens of milliseconds; low‑latency codecs like aptX LL help but are not always supported, and not on all Apple gear.[arylic]
• Resync behavior: If packets drop or the RF environment is noisy, the device may slightly resync or rebuffer audio, which can show up as drifting lip‑sync on longer sessions.[fpdvision +1]
Some platforms, including recent Apple TV models, use calibration routines (like the iPhone proximity test) to measure Bluetooth/ARC latency and compensate, but only if you run them.[reddit +1]
Why it feels so universal now
A few structural changes in how we watch content make these issues much more visible than in the analog/broadcast era.
• Everything is digital and post‑processed: Old analog TV carried audio and video in one continuous signal chain, with almost no per‑component buffering; modern systems are packets, buffers, and processors stacked on top of each other at every stage.[tcl +1]
• Multiple hops and ecosystems: A single viewing setup might involve: streaming app → CDN → ISP → modem/router → streaming device → TV → ARC/eARC → soundbar. Every hop can contribute either jitter or a small fixed delay.[fpdvision]
• Bigger, sharper screens: On a 55–77″ 4K panel, we naturally focus on details like lip motion and ball impacts; what was invisible on a 27″ CRT is obvious now.
• Live streaming latency tricks: Services will sometimes alter buffering strategies for “low latency” modes in sports, which can affect how they schedule audio vs video at the client.[facebook +1]
So from your perspective, it feels like “everything is out of sync everywhere,” but underneath it’s the cumulative effect of many small, separate timing decisions.
Why it happens on your devices specifically
Given your setup (Apple ecosystem, streaming, sports), the most likely repeating patterns are:
• Apple TV + TV + (possibly) external speakers:
• TV doing heavy motion smoothing/upscaling for live sports while audio goes through ARC/eARC to a soundbar or receiver.[whizz-experts +2]
• Apple TV outputting Dolby Atmos/5.1 while ARC path is marginal, causing extra audio processing delay.[sony +1]
• Wireless Audio Sync either not run recently or thrown off by changes in the room/setup.[youtube +1]
• iPhone/iPad watching via Bluetooth headphones or AirPods:
• Bluetooth codec latency plus additional processing (spatial audio, head tracking, noise cancellation) making the sound lag slightly behind video.[arylic +1]
• App/service quirks with sports:
• Live sports apps (YouTube TV, ESPN, etc.) occasionally shipping streams with slightly misaligned timestamps or messing up around ad breaks; pausing or rewinding a bit often temporarily “snaps” them back into alignment.[facebook +2]
Put together, it’s not one single “defect” but a series of small mismatches that you, being detail‑oriented and sensitive to timing, are consistently noticing.
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Even if half of the above is hallucination, the half that's fact is way more than enough to discourage anyone with a modicum of common sense from fiddling around with the advanced controls and calibrations alluded to.
I've decided to live with the asynchrony because trying to fix so many different possible causes can only lead to catastrophe once I start fiddling around with the specialized settings in all my devices.
I urge you to do the same.
Next slide please....
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