TrueHD Lip Sync feels off after the latest update

After updating to v1.1.42 I watched a 4K Blu-ray with TrueHD Atmos, and the audio definitely didn't feel properly synced to the video. Lip sync was pretty noticeably off, and it was very obvious with the timing of certain sound effects. I'd say it's probably off by around 150 ms. Has anyone else also noticed this?

 

checking. Will fix it in the next version

 

Thank you, mirror! I really appreciate the quick response. I should've also added that I'm using the Z9X 8K, and the movie with the issue was the 4K Blu-ray of "Eternals" in mkv format.

 

I confirm this which makes me cry because it was so synced perfectly before. It seems like Atmos/DD+ is not affected, only Atmos/TrueHD and it’s not the 24fps problem either since the files I am testing are 23.976fps.

I will test this more when I start using the Z9X 8K for longer periods of time.

 

I'm unable to test until later tonight, but here is a good TrueHD test sync file from the Spears & Munsil disc

 

Yeah, let's not post links to copyrighted material unless it's under Fair Usage.

 

Fair enough, thought it'd be okay since it's a short test clip

 

I tested the clip that @theory sent me and somehow that was perfectly in sync. I also have the Spears & Munsil disc, and the Sync test in that was also spot on. But I'm 100% sure that the sync was off when I watched the 4K Blu-ray of "Eternals". Not sure what's going on here, hopefully the dev team can pinpoint what's causing the sync issue in certain files.

 

Is that spears and munsil clip using truehd/atmos? If not you may not see the lip synch issue.

 

It appears to be TrueHD 5.1 without Atmos. I also watched a movie with TrueHD 5.1 and it was perfectly in sync. The movie that was out of sync was "Eternals" with TrueHD 7.1 Atmos.

 

In the early days of the Z9X Pro, all movies with Atmos/TrueHD was stuttering. Zidoo found the problem and fixed it. This is a different issue but it might be related to that Z9X Pro bug somehow. The thing is, sync was perfect in previous firmware so they should be able to fix this.

I tested more movies with different sound formats. The only format with which I have lip synch issues is Atmos/TrueHD. No lip synch issues on Atmos/DD+ or standard TrueHD without Atmos or DTS-HD MA. Seems to be specific to Atmos/TrueHD. Again, I'm almost certain Atmos/TrueHD was perfectly synced with the original firmware before 1.1.42. Hope this narrows it enough for the Zidoo team to look into this. @mirror already said he's looking into this so let's hope for the best.

 

@Draconix what does your hdmi connections look like? I have z9x 8k -> yamaha avr -> tv with only video going from avr to tv.

 

Tried the new 1.1.47 firmware and still have the lipsynch issue.

If I add a 150 ms DELAY using the audio offset function, then my TrueHD movies becomes in sync but that makes the other videos not using the TrueHD codec out of sync with audio playing after the image and makes me need to switch back the audio offset from 150ms DELAY to 0 ms depending on which movie I play which is a pain.

The 1.1.47 firmware seems to have fixed the audio sync issue with TrueHD for some people like for @Alan Bates but not on mine unfortunately.

I hope @mirror and the Zidoo devs can continue to check for this issue and make more corrections please?

Tagging @Eki Shaw also here so he can see this and help out please?

All my files are MKVs.

P.S. I re-re-rechecked the TrueHD playback on my Z9X Pro using the very same TrueHD movie files on the very same "Player -> AVR -> TV" setup and they play perfectly in sync.

 

I just wanted to add I also have the Z9X 8k which I setup yesterday. I didn't note the firmware version I think it was 1.3 something. A few tests seemed to play everything fine. I then updated to the latest firmware (non-beta) and immediately now every film turns subtitles on when you first play it and the lip sync issue is terrible on TrueHD and slightly out on DTS HD Master Audio. Literally 99% of my movies are now unwatchable. I also tried the latest beta firmware and it's still the same with the subtitle issue and the lipsync issue. The only audio that seems to be in sync that I have tested so far is Dolby Digital Plus, this particular audio track had Atmos as well and all good. These files work fine on all other players so it's not the files themselves.

Edit for reference the audio plays ahead of the video. The subtitles show on every film even if you specify in the beta software no subtitles, you still have to manually turn them off.

 

So you confirm then that on original 1.3.38 firmware you had no lipsync issue on true hd and dts hd? That’s what I remember but I can’t test with 1.3.38 anymore so I wasn’t 100% sure.

 

Has there been any more info on this? I'm experiencing the same thing where audio for TrueHD/Atmos files isn't synching up properly on my z9x 8k. It was always fine on my z9x Pro.

It doesn't seem to be all TrueHD/Atomos tracks, but two I've found the problem on for sure are Top Gun Maverick and Blue Beetle.

Chain is Zidoo --> Anthem MRX 520 --> LG C8.

Changing offset back (not forward) by about 150ms seems to fix it, but then of course breaks it on every video without the problem.

Firmware is 1.1.47. I did not look for this issue before upgrading, so can't say if the current firmware broke it or it was broken out of the box.

If there is a freely available video file that I can use to test with, let me know. I know that it can be hard to fix these things without a reproducible test.

 

The devs & I have been unable to replicate this until very recently when a post pointed me in the right direction.

I can only replicate with Dolby Vision files and only if I skip backwards on the timeline say 30s or so using arrow keys. This introduces a 3 frame (125ms) difference between video and audio.

Skipping forward on the timeline then fixes the delay.

A TrueHD delay/advance feature was added to test firmware as a pro tem fix but I don't think it's any use given the above.

 

After a bit more testing, it seems to be every TrueHD/Atmos file. I guess some of them are a bit tougher to notice. HDR or Dolby Vision has no impact on this. I have movies with just HDR that are affected and Dolby Vision ones that are affected. Dolby Digital and DTS-HD are fine.

Strange that this would affect a limited number of people and not everyone. For me, it's very easy to reproduce. Would source have anything to do with it? All my files are stored and accessed via an SMB share.

Also skipping back and forth has no effect in terms of causing the issue or fixing it.

 

Yeah, it's strange when Mark says it seems to be DV-related in his testing because that's not what I'm seeing at all. I wonder if different user settings would have any bearing on how the issue presents itself. I can also support the finding that fast forwarding seems to fix it.