Skip to main content
I
Inrot
Participant
March 3, 2017
Answered

Audio out of sync when exporting H.264

  • March 3, 2017
  • 24 replies
  • 160585 views

I just discovered the following:

Whenever I export a H.264 in MP4 container, the audio in the resulting file goes about 10 ms out of sync. (575 audio samples to be exact.)

Screenshot:

Green is the original clip, red is the resulting file from export.

I used 25fps in export settings.

To test this I used:

  • HD bars and tone that lasts exactly 1 frame @ 25 FPS
  • Cleared / reset the cache
  • Disabled the h.264 acceleration in settings and restarted premiere
  • Rendered the timeline to green
  • Tried to render with Adobe media encoder

The result was always the same, audio is not in sync with the original timeline.

To see if it's just a display issue, I copied the empty space in the start of audio, pasted it 100 times and it was silent. I also brought the video file to cubase and the desync was clearly there as well.

I tried other codecs and they all worked fine and are 100% in sync, including H.264 in .MOV container.

The video is exactly the same in the resulting file and lasts for 1 frame as it's supposed to, the audio starts 10ms late.

I tried to export audio only as MP3, that made the audio go even further out of sync.

I've gotten similiar files from my coworkers using adobe premiere, which is telling me that this is not a problem with my system only.

What is the cause of this and can it be fixed?

      Correct answer roberth63696283

      It was driving me crazy, but I found that VLC played it perfectly.

       

      24 replies

      Show previous replies
      chriscardinal
      chriscardinal
      Participant
      July 5, 2017

      This is vexing. I'm attempting to export a project with an MP3 as the audio and the export includes the audio, but offset to exclude the first 1.5 or so seconds. This appears to happen just on H.264, with the most updated version of CC.

      I've even attempted to create a brand new project, and just export the audio with the MP3 the ONLY thing in the sequence, and it STILL failed to render out the first 1.5 or so seconds. This is insane, and I have to think some sort of bug with the encoder.

      Exporting as MPG resolves this. Completely confused.

        epensenstadler
        epensenstadler
        Known Participant
        April 29, 2017

        I'm all of the sudden having sync issues too, thought it appears to be any export format (video or audio), and, it appears that it gets more and more out of sync the longer the video.  For example, I'm trying to export a 2 minute video and the beginning is just fine but then the sync gets worse.  I have not updated Premiere recently and this has not been an issue before.  I literally just started happening and again, it's not only h.264.

        Eric

          epensenstadler
          epensenstadler
          Known Participant
          April 29, 2017

          UPDATE:  I just did 3 minor changes in my export settings and the audio and video were back in sync.  I will share below.

          CHANGES: 

          1)  I did what other recommended and I did the Render and Replace.

          2)  In Media Encoder I simply cleared the Media Cache Database.

          3)  I UNCHECKED the "Keyframe Every" option in the video settings.  This shouldn't make any difference, but it's something I changed and therefore I'm noting it here.

          I should have done the above one at a time to better narrow down the issue, but alas it's only 3 things - none of which should cause the audio and video go out of, or back into, sync upon exporting.

          FYI SETTINGS:

          h.264

          23.976 fps

          1920x1080

          Audio exporting as AAC, 48KHz, 160 Bitrate

          Just sharing my update.  Really not sure what the difference was but all I know is that my last export was the first time this project exported IN sync.

          Eric

            E
            excited_Genie16B8
            Legend
            March 3, 2017

            Based on your waveform, that's not the default audio for Bars and Tone.  What audio are you using for the test?

            S
            SAFEHARBOR11
            Participating Frequently
            March 3, 2017

            Jim, that is the correct waveform - he is zoomed in on Audio Time Units, so you are seeing actual sine wave rather than the straight line seen in frames view. Just tried it here. Able to fully duplicate his issue (although I am exporting more than one frame, I went a whopping 15 seconds).

            I
            InrotAuthor
            Participant
            March 3, 2017

            Yes, this is correct. It's the default audio for Bars and Tone, just zoomed in.

            Peru Bob
            Community Expert
            Peru BobCommunity Expert
            Community Expert
            March 3, 2017

            You may want to file a bug report:

            Feature Request/Bug Report Form

              I
              InrotAuthor
              Participant
              March 3, 2017

              I made a bug report as this issue clearly seems like one and has been duplicated by few people already.

                E
                excited_Genie16B8
                Legend
                March 4, 2017

                I'm seeing the same thing here.  Doing some testing, the issue seems to affect all compressed audio formats.  It does not affect uncompressed audio formats.

                Terms & ConditionsAccessibility statement
                Using the community Terms of use Privacy Cookie preferences Do not sell or share my personal information ad choicesAdChoices