Lip Sync Problems

Hello everyone,

I’ve been using infuse for around the last year and im wandering if anyone can help me troubleshoot a problem thats been plaguing me since day one.

In short, im getting a very subtle lip sync problem when trying to watch some videos. I think the audio must be behind because i cant seem to fix it using delay setting. The files it happens with are typically large 4K files but ive had it happen with smaller 1080 files. All the files are MKV and its happened when the audio codec is ac3 and other formats like DTS/TrueHD etc. Basically, what im trying to say is it can happen both when the audio stream is transcoded and when its not transcoded. As i said, the error is only very small but once aware of it, its incredibly frustrating.

Before i go further let me explain my setup. Its very simple. I have a Sony XF9005 television which outputs over HDMI to a Sonos beam setup in 5.1. The appleTV is plugged into the TV over HDMI And in the apple tv setting i have the audio output set to dolby digital 5.1.

Tbh, ive done a massive amount of troubleshooting and ruled out so many things. I wont list everything Ive done but the biggest evidence this could be a problem with the app is that I literally have no problems with lip sync except when using infuse - this is across not just other apps on the apple TV but other inputs such as digital television etc. Im actually using infuse to connect to my plex library and when i view files directly in the plex app they play fine. I basically just use plex now due to this issue but i love the infuse app and just wish this problem could be fixed.

Can anyone help? Im wandering if the is widespread but many people just arent bothered because it is rather subtle. But its definitely there and watching the same file in both infuse and another app like plex makes it incredibly obvious.

1 Like

You can try Apple TV new audio sync:

Also it could be a problem with the movies themselves. I know I have some movies that have real audio problems, but it’s not a sync problem, just bad mixing.

Thanks for the help but as is I said, its really just a problem with the infuse app. Ive noticed that in at least one of the release notes there has been a mention of improved audio sync with ac3 files. Im wandering whether this is somehow related.

Next time you notice a problem try to look up the details on the audio. If we find a pattern then maybe we can fix something. You can use an app like Media Info to give you exact specs on the audio/video.

Additionally if these are movies you are converting/encoding yourself make sure you are using the latest versions for all of your software. Old encoders have been known to cause issues.

I just thought id provide a little update on this.

As mentioned before, due to the issue, which ill say again is very very subtle but still off putting, ive been using plex on the apple tv.

Plex still had a very slight problem but so small i could forget about it most of the time.

However, today i tried the enhanced video player that plex users can access if they have a pass. Its literally the first time in a year ive finally been able to watch all films 100% perfectly with no issue at all. I feel like ive found the holy grail! Apparently the key difference when using the enhanced player is that it uses direct play a lot more. But i thought this was strange because isnt that how infuse functions?

This is probably a pointless post but i just thought id share it. Whatever plex enhanced video player is doing differently to infuse has solved my problems. Maybe it can be looked into by the devs. I hope i can use infuse again one day but for now this is my solution.

Sorry for the trouble.

Do you find this is consistent throughout the movie, or does it get worse as time goes on?

Any chance you’d be able to send in one of the problematic files for us to review?

Tbh its happening with virtually all files so im not really sure theres any point uploading anything.

The lip sync problem is very very subtle (most of the time at least), with the audio slightly trailing the video. My partner cant even really notice it but for me its very off putting. Originally i thought it was a limitation of my hardware: with the delay being caused by a mixture if the TV passthrough and sonos wireless setup. However, plex was noticeably better and streaming services like netflix, prime, iplayer were perfect. Then i tried the enhanced player from plex and thats perfect now as well. Its so frustrating because i love infuse and i think it provides a better picture quality than plex. Im guessing something fundamental under the hood is just causing a slight delay (possibly just with my setup but i cant imagine why).

Is there any major plus point for Infuse over say MrMC? I had lipsync problems with local files from the first day I bought an Apple TV but since MrMC can adjust the audio/video in both directions it was just easier to give up on Infuse and use MrMC for all local files.

Having the same problem:
My setup

  1. Apple TV 4K 64GB, Infuse Pro, Synology NAS - 4K Movies have a lip sync problem
    → what helped but didn’t solve the problem: turned “4K motion enhance” off on beamer (Benq w2700/HT3550) and did an Apple TV audio sync
    → 1080p movies are ok now

  2. Nvidia Shield TV 2019, Kodi, Synology NAS - same 4K movies do NOT have the lip sync problem

  3. & 2) no lip sync issues with Netflix

@Firecore…any ideas?

I have the same issue too in Plex using the enhanced player, so I just bought Infuse hoping to get rid of the lag but sadly it’s present here too.

Interestingly if I switch to the standard Apple player in Plex, there’s no lip sync issue. That’s what I’ll be using for the foreseeable future but it’s unfortunate.

I’m having the lip sync issue too.
Lg projector connected to Apple tv4k to a Sonos via optical cable. Every app besides Plex and Infuse works correction .

I know this is a pretty epic thread bump but I’m quite new to Infuse and this almost exactly describes the issue I’m currently seeing with Infuse. This is via HDMI ARC.

Practically all files play with an almost insignificant but noticeable audio delay (audio late); possibly one or two frames late. It seems to be an issue localised to just Infuse as all other apps I’ve tried (Disney, Apple TV, Netflix, Amazon) are in sync.

It seems the problem is exacerbated by the combination of Match Frame Rate and the conversion of audio to Dolby Digital 5.1. If I do not convert audio (and set it to Auto), Infuse is in sync but all other apps have audio early. I can’t seem to win no matter what option I set. If I turn off Match Frame Rate then all apps are in sync except Infuse which has audio late again.

What I’ve tried:

Convert audio DD5.1, match frame rate ON: Infuse desync. Others sync.
Auto audio, match frame rate ON: Infuse sync. Others desync.
Auto audio, match frame rate OFF: Infuse desync, others desync.

Happy to provide logs if needed. Ideally an audio sync option in Infuse to set up a delay would be ace. Or at least an understanding of why this seems to be an issue.

I’m thinking we need some scientific basic for understanding the issue with measurements. I’m thinking that this could also be partially subjective because the speed of sound is slower than light and perhaps some are expecting it too soon? I dunno…we are talking ms at this point.

Anyways, try downloading this and running it through various places, post a picture of frame where it hits with audio waveform so we can take a look. (Is someone has a better one feel free to post)

Ill have a look at this too. Its been a long time since i started this topic but the problem persists. If i compare Plex and Infuse for the same file, infuse always has an audio delay. It is slight but noticeable. Im really not sure how things are working on the back end but ive been wondering something. In the system menu for the apple tv, i have to set audio to change format: Dolby Digital. If i dont do this i wont get DD 5.1 being sent over HDMI ARC to my sonos beam. How exactly does this setting work? Does this force apps to provide a DD 5.1 stream, or can apps provide any natively supported stream (DD, AAC, PCM) and then the apple TV encodes the audio on the fly to DD when its not already in that format? I only ask because if this is the case, it could explain the difference between infuse and plex. Is plex providing a DD 5.1 stream whereas the apple tv is having to do additional processing for infuse because its its only providing PCM, and this is introducing a delay?

Thanks for the file, I’ll have a look at it using various settings and apps.

Just thought id provide an update. I recently switched my X900F for an LG B9. All the settings on the Apple TV are exactly the same using the same cables. The problem is now gone. I no longer have any lip sync problems. It seems strange that when using the X900F, the audio sync was okay with plex but not infuse. Does infuse do something unique in terms of how it interacts with the TV?

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Thanks for the follow up!

I’d guess there is some setting on your X900F somewhere buried in the pile that may be the culprit. I had a similar experience with color settings on my LG after thinking I had it “dialed in”. Certain videos would look nasty for no reason I could see and I blamed Infuse until I did a reset on the tv and presto, theater quality video. One of the “custom video” settings was causing only certain videos to be poorly rendered.

Glad you’re back on track with the timing!

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