Are AV synchronization issues a problem?

[dcoke22]

I get it. You've made a decrypted backup of BttF Part II. When you do option A, you get a .mkv file with audio dropouts. When you do option b, you get a .mkv file without audio dropouts.

Run the command (substituting names and file paths as appropriate):

Code: Select all

mkvinfo -C optionA.mkv > optionA.txt

and

Code: Select all

mkvinfo -C optionB.mkv > optionB.txt

The tool mkvinfo is going to produce a lot of text data about the .mkv file. '> optionA.txt' is the part of the command that captures the output and saves it in a text file. Compress both text files to save space and send them to Mike. This is the developer of the program asking you for data so he can take a look at the problem you've identified and potentially fix it.

[Legenista]

OK, these are the files requested. Use 7-zip or WinRAR:
https://www.dropbox.com/s/qbxm7tqd4wt2w ... 4K.7z?dl=0

First file has 540 MB, second has 82.

For optionA I selected the Atmos track, DD 5.1 derived from it, and also the 2 commentary tracks. And the english subtitle.

For optionB I didn't select the Atmos track. Included: DD 5.1 derived from the Atmos, the 2 commentary tracks, and the english subtitle.

What is really odd now is that I am not seeing any sign of the bugs reported before. That doesn't mean they aren't there, because MAKEMKV said A/V SYNC ISSUES at the end of creating each MKV.

In the scene I said there was a very quick freezing it's normal in both files. So this could mean the bug has moved to other part of the file.

If you verify both of these "logs" and can't find anything wrong despite of the A/V SYNC ISSUE from MAKEMKV, then I am confused why I am not seeing it again.

Or...

It could mean MKVTOOLNIX is what's messing things here, and has damaged the file or isn't handling Atmos tracks properly, especially if we split them.

[bjaurelio]

I had AV Sync issues with The Martian. However, when I tested the first few locations where they are at I did not notice any glitches with the movie over Plex. I did try the theory that the subtitles could be a problem and ran it a second time without subtitles. It gave me the exact same AV Sync errors.

Saving 1 titles into directory E:/Videos/Movies
AV sync issue in stream 1 at 0:18:12.050 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +0.652ms
AV sync issue in stream 1 at 0:21:19.946 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +1.233ms
AV sync issue in stream 1 at 0:38:03.657 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +0.98ms
AV sync issue in stream 1 at 0:40:08.156 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +0.65ms
AV sync issue in stream 1 at 0:58:03.397 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +0.65ms
AV sync issue in stream 1 at 1:13:09.385 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +0.666ms
AV sync issue in stream 1 at 1:16:05.353 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +0.652ms
AV sync issue in stream 1 at 1:33:57.049 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +1.027ms
AV sync issue in stream 1 at 1:37:20.877 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +0.647ms
AV sync issue in stream 1 at 1:53:19.960 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +0.666ms
AV sync issue in stream 1 at 1:58:09.375 with duration of 1.666ms : 2 frame(s) dropped to reduce audio skew to +0.652ms
1 titles saved

[saracen]

Having the same issue AV is completely

[Legenista]

So, any updates on this? Can someone at least confirm if this is a bug from MAKEMKV, a problem handling the discs perhaps due to a stronger protection (?) or they are all defective? Or perhaps a great number of discs are spoiled, and others are OK?

Other users also had problems with this BTTF UHD boxset:
viewtopic.php?f=12&t=23464

[preserve]

So, any updates on this? Can someone at least confirm if this is a bug from MAKEMKV, a problem handling the discs perhaps due to a stronger protection (?) or they are all defective? Or perhaps a great number of discs are spoiled, and others are OK? Other users also had problems with this BTTF UHD boxset: viewtopic.php?f=12&t=23464

I don't remember folks having AV sync problems with the BTTF discs, just problems reading the UHD discs, which were resolved when the discs were cleaned? I don't see any mention of AV sync in the thread you linked.

Regarding trouble reading the discs, that would be a different issue, and could be related to the discs, the drive, the read speed (for particularly troublesome discs, which could be a manufacturing issue), or a combination of all three. But some folks (such as myself) had zero problems with the set, and I wouldn't expect everyone who had no problems to post, as generally people post when they have issues, not when they don't.

As far as updates go, Mike is pretty quiet on the forums. He's already mentioned in this thread that 1.15.4 is coming soon and should address the issue. I'm sure there's many people waiting so they can re-rip their Atmos discs, and Mike offered a test version if you PM him, which isn't something he's often done. Obviously he wants to get this fix right before releasing it. This pace is the way it's always been, and since presumably being less active on the forums means he has more time for MakeMKV development and resolving these issues, then personally I've always been okay with that.

[Legenista]

So, any updates on this? Can someone at least confirm if this is a bug from MAKEMKV, a problem handling the discs perhaps due to a stronger protection (?) or they are all defective? Or perhaps a great number of discs are spoiled, and others are OK? Other users also had problems with this BTTF UHD boxset: viewtopic.php?f=12&t=23464

I don't remember folks having AV sync problems with the BTTF discs, just problems reading the UHD discs, which were resolved when the discs were cleaned? I don't see any mention of AV sync in the thread you linked.

Regarding trouble reading the discs, that would be a different issue, and could be related to the discs, the drive, the read speed (for particularly troublesome discs, which could be a manufacturing issue), or a combination of all three. But some folks (such as myself) had zero problems with the set, and I wouldn't expect everyone who had no problems to post, as generally people post when they have issues, not when they don't.

As far as updates go, Mike is pretty quiet on the forums. He's already mentioned in this thread that 1.15.4 is coming soon and should address the issue. I'm sure there's many people waiting so they can re-rip their Atmos discs, and Mike offered a test version if you PM him, which isn't something he's often done. Obviously he wants to get this fix right before releasing it. This pace is the way it's always been, and since presumably being less active on the forums means he has more time for MakeMKV development and resolving these issues, then personally I've always been okay with that.

This is what is most strange about this problem, the fact some people had A/V sync issues even if there was no Atmos track involved.

Whatever this bug is, I hope it can be fixed for good, or at least that mike identifies for us what the hell is going on, because this is the first time EVER I rip a movie and later discover the rip has been "damaged" somehow.

When I tried the first time I noticed audio dropouts, a quick freezing, and at the time I didn't assume this was due to MAKEMKV or the BDMV folders having some shenanigan going on. Later I played the movies from the mts files and didn't notice anything wrong.

Mind you, I was only able to spot this bug after I did my usual splitting to fit 15 GB free Google Drive accounts, for UHD/4K movie contents. Otherwise I would have to watch the whole thing to see if there was something wrong.

To make matters worse I saw some users saying this was only a false alarm from MAKEMKV, as if this was only MAKEMKV scaring us for no reason, and in the end the rip was just fine. Not only it's not fine, we need to comb the entire rip to spot the reason behind the "A/V SYNC ISSUE".

And in my case "A/V SYNC ISSUE" without the specification of which moments of the movie.

Of course none of this is mike's fault, shit happens, it's just frustrating to see that official discs are still causing trouble.

[preserve]

the fact some people had A/V sync issues even if there was no Atmos track involved.

AV sync issues can occur whenever the playlist consists of multiple segments, but excepting the recently-diagnosed Atmos issue, MakeMKV should generally be handling them adequately. Personally, I always save the log (as well as an output of the disc structure and file listing) with each rip, so that I can go back to any rip and look at which version of MakeMKV I used and any issues that may have come up.

And in my case "A/V SYNC ISSUE" without the specification of which moments of the movie ... I noticed audio dropouts, a quick freezing ... my usual splitting to fit 15 GB free Google Drive accounts

The log shows you the timecodes when the AV sync errors are occurring. You may want to check your Preferences to ensure that "Log debug messages," "Expert mode," and "Show AV sync messages" are all checked. If you're not seeing any messages but you're still noticing audio dropouts or freezing, it may be a different issue.

To make matters worse I saw some users saying this was only a false alarm from MAKEMKV

There is a known false message about AV sync issues but it's easy to identify. If the message appears but the subsequent messages are just regarding forced subtitles being empty and removed, then there is no AV sync issue. Hopefully this false message appearing should be resolved in the next version.

[Legenista]

AV sync issues can occur whenever the playlist consists of multiple segments, but...

Following your tips I created a log while attempting to rip BTTF part 2 again.

The file is short, yet the messages now reveal more about this issue.

I have attached here what it says, and you can also read here:
https://pastebin.com/wHehL9Qi



So...

004047:0010 AV sync issue in stream 3 at 0:00:00 : 0 frame(s) dropped to reduce audio skew to +22ms
004047:0010 AV sync issue in stream 4 at 0:00:00 : 0 frame(s) dropped to reduce audio skew to +22ms
004008:0010 AV sync issue in stream 3,4 at 0:00:00 with duration of 22ms : encountered overlapping frame, audio skew is +22ms

Wait a minute... streams 3 and 4 are from the audio commentaries... right?

Does that mean the rest is OK? I'll try doing another rip, this time not selecting them...

[Legenista]

As you can see, it says A/V sync issue and nothing more... so if the audio commentaries had a problem, then why still the warning?

New log:
https://pastebin.com/JPyt9drx

and attached.

Well, I'll be waiting for a fix, because this is a deeper problem. What was very odd is that only after following these 3 tips I saw for the 1st time something more than "A/V sync issue".

[Legenista]

As you can see, this is a widespread issue. Another unrelated title, Total Recall (1990) in UHD/4K, showed the same warning. And once again it's not saying when this A/V sync issue happens, only that is there, read the log.

And this title also has one Atmos track. But now please note more than one title (not just the movie) has the same warning. This is the 1st time I also see the warning for extra features, too.

Titles 2 and 19 are bonus contents. The first has 9 GB and the second 1 GB. The first 59 minutes, the second 8.

That just proves it's not the movie itself that is affected by the bug. And in case you are wondering, title 19 has another type of audio track:

Audio
ID : 2
ID in the original source medi : 4352 (0x1100)
Format : PCM
Format settings : Little / Signed
Codec ID : A_PCM/INT/LIT
Duration : 8 min 26 s
Bit rate mode : Constant
Bit rate : 1 536 kb/s
Channel(s) : 2 channels
Sampling rate : 48.0 kHz
Frame rate : 30.001 FPS (1600 SPF)
Bit depth : 16 bits
Stream size : 92.7 MiB (7%)
Title : Stereo
Language : English
Default : Yes
Forced : No
Original source medium : Blu-ray

Log from Total Recall:
https://pastebin.com/x7UKW1mF

Since this problem keeps happening, I'll wait for a fix and don't try to rip UHD's anymore. That is, of course, if this is only happening with 4Ks.

Important: I have not checked any of the Total Recall files to see if there's some abnormality during playback. Could it be all of them are 100% OK, the problem is that it takes a lot of time to do this checking. Remember when I said there were audio dropouts, and very quick freezing in the video? If we don't know where they are, and the movie has 2 hours, that means you need to sit through 2 hours and for each audio track. Unless of course there are other ways to verify this, quickly.

[sofakng]

I'm also having issues with a brand new LG WH16S40 drive and MakeMKV 1.15.3.

Coco UHD gives me about 10x AV sync issues, and Back To The Future UHD gives me 'Source file is corrupt/invalid' issues.

[Legenista]

More issues. This time with a UHD/4K that doesn't even have Atmos, only DTS-HD MA:
http://dvdcompare.net/comparisons/film.php?fid=55853

Beverly Hills Cop, 1984. Recent release.

Here's the log:

https://pastebin.com/inUTrpxK

It's really sad how these problems are pilling up. Either MAKEMKV has a lot of things to fix based on newer disc releases, perhaps with some protection enabled that triggers these sync issues, or we are seeing many discs somehow defective. All the logs I posted here were decrypted folders.

I was going to ask if it would be any different extracting the audio/subtitle tracks from the m2ts files, using another program. Or even the video stream, and then saving as MKV.

But I guess this would not make any difference, perhaps because the files are already broken, even as decrypted folders? If they are not, is it MakeMKV the one creating the A/V SYNC ISSUES?

This is really bad, Mike. It's the 1st time I use this program and see so many titles with the same problems.

[dcoke22]

viewtopic.php?f=1&t=23937

[Legenista]

viewtopic.php?f=1&t=23937

I'll repeat what I said there here, in case I am not making myself clear:

Even if this is a false alert for 90% of titles, it's also a problem.

Why? I'll explain: When I ripped BTTF part I which has the Atmos track, there was no way to fix this. Apparently the only solution was to let all other tracks in the MKV file, including the DD 5.1 derived from Atmos. If I do that I don't see the audio dropout bug.

However BTTF part II I ripped twice and the first time (note: also has the same A/V SYNC ISSUE warning) I noticed a very quick freezing in a specific moment of the movie (less than 500 ms for sure). The 2nd time I didn't notice. The Atmos track is still there.

That doesn't mean:

- MAKEMKV isn't damaging the end result in any way;
Or
- The disc isn't flawed/defective, which may explain why MAKEMKV says A/V SYNC ISSUE. The disc could be messed somehow.

For BTTF part I thought this was a false alert, after reading posts from here.

Did you know how I discover this was not the case?

Not by watching almost 2 hours from the movie, and 120 minutes for each track, and noticing if there was something wrong.

I discovered there was something wrong only if the Atmos track was there in an unusual way:

- By splitting the 4K MKV file into 15200 MB parts, using MKVTOOLNIX, to put these splitted parts in Google Drive free accounts.

So I opened part 4 and right at the first seconds there was audio dropout. And there was image freezing lot longer than 0.5 second. In fact, SECONDS.

This bizarre bug affected the video as well, as if the Atmos was a virus damaging anything in its path.

If I hadn't opened the files I would never had spot any of this in the 1st place.

So, when we read things like that:

*********
Yes, ignore it. It's an informational message most of the time anyway. Unless you're dealing with Atmos... And it only means something if a track and location are present.
*********

We assume everything will be fine... until we check if MAKEMKV's warnings hold any water.

Also, from the looks of it this is not an Atmos bug:

Sat Dec 14, 2019 from this thread...

Says:

*********
I've seen these issues come in with UHD rips as well in the last few days, and in all cases none of the rips have included an Atmos track. They've been DTS-HD, and the Blu-Rays I have tested have all been DTS. I'll be sure to test some Dolby back-ups today.
*********

So, to sum things up:

- All these discs can't be defective. What are the odds?

In my case all MAKEMKV use is done with the folders from 4K/BD already decrypted and stored in my SSD.

Logic then tells me this is MAKEMKV's fault, which is not doing what needs to do properly, perhaps due to some inconsistency in certain titles, which trigger these warnings and result in a few cases broken tracks that may or may not affect the video as well.

Unless this bug is fixed then we can never trust the MKV rips we get again.