Given:
Kdenlive 16.12.2
MLT 6.5.0
KDE Frameworks 5.18.0
Qt 5.5.1 (built against 5.5.1)
The xcb windowing system
Ubuntu 16.04

I created my video in editor. All seemed well. No lag in preview. The rendered version has audio occurring before video. It gets worse toward the end of the video.

It seems the out of sync issue progressively gets worse. You might notice minor of out sync issues about mid-video and then it's full blown out of sync by the end of the 1 hour video.

I tried the trick where you extract the audio using ffmpeg and then lay down on the audio track. Same results. Tried rendering to different formats. No change.

Any suggestions on how to fix this?

Try to convert the extracted audio to wav and use wav in kdenlive. Sometimes there are problems with variable bitrate audio streams.

capslock wrote:Try to convert the extracted audio to wav and use wav in kdenlive. Sometimes there are problems with variable bitrate audio streams.

Thanks. That's what I did. I extracted to wav using ffmpeg (390MB wav file) and then added to an audio track. Same result.

kylem wrote:Given:
Kdenlive 16.12.2
MLT 6.5.0
KDE Frameworks 5.18.0
Qt 5.5.1 (built against 5.5.1)
The xcb windowing system
Ubuntu 16.04

I created my video in editor. All seemed well. No lag in preview. The rendered version has audio occurring before video. It gets worse toward the end of the video.

It seems the out of sync issue progressively gets worse. You might notice minor of out sync issues about mid-video and then it's full blown out of sync by the end of the 1 hour video.

I tried the trick where you extract the audio using ffmpeg and then lay down on the audio track. Same results. Tried rendering to different formats. No change.

Any suggestions on how to fix this?

How did you obtain Kdenlive, or did you compile it? Could the issue be in MLT 6.5?

farid wrote:

kylem wrote:Given:
Kdenlive 16.12.2
MLT 6.5.0
KDE Frameworks 5.18.0
Qt 5.5.1 (built against 5.5.1)
The xcb windowing system
Ubuntu 16.04

I created my video in editor. All seemed well. No lag in preview. The rendered version has audio occurring before video. It gets worse toward the end of the video.

It seems the out of sync issue progressively gets worse. You might notice minor of out sync issues about mid-video and then it's full blown out of sync by the end of the 1 hour video.

I tried the trick where you extract the audio using ffmpeg and then lay down on the audio track. Same results. Tried rendering to different formats. No change.

Any suggestions on how to fix this?

How did you obtain Kdenlive, or did you compile it? Could the issue be in MLT 6.5?

Thank you for responding.

I installed Kdenlive from the stable ppa. https://launchpad.net/~kdenlive/+archiv ... ive-stable

farid wrote:

kylem wrote:Given:
Kdenlive 16.12.2
MLT 6.5.0
KDE Frameworks 5.18.0
Qt 5.5.1 (built against 5.5.1)
The xcb windowing system
Ubuntu 16.04

How did you obtain Kdenlive, or did you compile it? Could the issue be in MLT 6.5?

I said MLT 6.5.0 because that's what Kdenlive reports, but Synaptic says 6.4.0. I don't even see 6.5.0 in a stable release.

This audio sync problem has been driving me nuts for over a year. Under 20 minutes of render, no problem.
Anything over 20 minutes the video and audio loose sync.
I have tried every version of ubuntu, kubuntu, lubuntu, arch, neon, mint and gentoo.
I have installed on several different systems, Pentium 4 on intel with intel graphics, ati graphics and nvidia and matrox.
Amd 8 core on gigabyte board nvidia 740 video. Intel 4770 on an gigabyte board ati x600 video card.
I have even tried on my dell laptop with xfce ubuntu and my acer laptop with mx linux.
If I do a short video all is well, over 20 min long and all hell brakes loose.
I have taken my source and converted from the source vob to dv, to mp4, to mkv to mov, tried every permutation
I have split the audio and changed from wav to mp3 to aac 41000 and 48000.
So far the only success I have had was to render in chunks and then join,,, this sucks.
Last night I took two intermediate 22 minute files that were rendered in lossless H.264 + aac and put then on the timeline
When I rendered without any edits, works great, audio sync to the end.
One edit and it all falls apart when rendered.
I like the interface but this problem makes kdenlive not fit for purpose.

I really love the app, its UI, workflow, etc., but it's worthless if it can't render correctly.

I just received 16.2.3 through the repo. Same problem.

gyrcom wrote:I have tried every version of ubuntu, kubuntu, lubuntu, arch, neon, mint and gentoo.
I have installed on several different systems, Pentium 4 on intel with intel graphics, ati graphics and nvidia and matrox.
Amd 8 core on gigabyte board nvidia 740 video. Intel 4770 on an gigabyte board ati x600 video card.
I have even tried on my dell laptop with xfce ubuntu and my acer laptop with mx linux.

This is disappointing as i was going to try Neon in a VM.

When I rendered without any edits, works great, audio sync to the end.
One edit and it all falls apart when rendered.
I like the interface but this problem makes kdenlive not fit for purpose.

I think you're correct. It's some combination of edits that start to trip up the renderer. The programmers are expecting projects to take A and B and not expecting C.

I thought Kdenlive would be the ONE. I have to hunt for a new editor.