3 Replies Latest reply on Nov 24, 2008 4:17 AM by (Olle_Lindell)

    Audio out of sync

      Hi!

      My main problem is that when I export from either after effects or premiere the audio gets out of sync by eight frames. The audio comes sooner than the video image.

      This problem arises when I have first exported the audio to sound booth, edited it, and then imported it again. However the strange thing is that the audio is IN sync when i RAM-preview it in After Effects or render it on the timeline in premiere. But as I export the project to whatever format mjpgb, wmv, mdv, the audio gets out of sync.

      The original audio used in the project is in 16 bit 48 khz mono, the audio is exported in 16 bit 48 khz stereo (in a quicktime container without image as I have realised that audio gets distorted at certain levels when using the export to wav function), then edited in soundbooth and exported in 16 bit 48khz stereo. With that said, no change in frequency is made anywhere (by the user anyway).

      To narrow it down:

      1. Exported video from After Effects and Premiere is in sync with audio while using the original sound (i.e audio embedded in a video footage from an interview).
      2. Exported video from After Effects and Premiere is out of sync with audio when a soundtrack has been exported, processed in soundbooth, and imported again.
      3. Audio is, in both cases, in PERFECT sync when ram-previewed in After effects or rendered on the timeline (or just played without render too) in Premiere.

      The audio is processed in soundbooth with normalization, limiting, noise reduction, and equalizing.

      Has anyone else had a problem such as this or am I doing something wrong?

      As a minor thing, has anyone else noticed that audio always plays out of sync while playing a wmv-file in windows media player for the first time? When you open the file and watch the first time, the audio is out of sync. If you wait for the video to load and play, then restart the clip (by moving the slider for example) the audio then gets in sync...

      I have the latest version of Windows media player, and use wmv 9 codec. However I have experienced this on different computers with different versions of the codec. I usually use variable bitrate though.

      I appreciate all the help i can get, thanks!

      / Olle
        • 1. Re: Audio out of sync
          Jonas Hummelstrand Level 2
          Put the AEP file and the WAV in a ZIP and upload it to something like yousendit.com and post the link here.

          The Render Queue should always be used for all formats that it supports. The Export function is a bit of a black box, you never really know what will come out the other end...

          - Jonas Hummelstrand
          http://generalspecialist.com/
          • 2. Re: Audio out of sync
            Level 1
            Sorry if I mixed up the expressions, I never use the "export" function I meant that I exported video from after effects by rendering...didn't even think of the crappy "export" function.

            And sorry I can't publish my project as it is already delivered to the customer (we solved the non sync temporarily) and I don't really have the right to give the source material to anyone outside of our company.

            Maybe I can get a sample for you, with only the original audio, edited audio and rendered video stream, but I have to check that with my superiors first.
            • 3. Re: Audio out of sync
              Level 1
              Hey again!

              I have cleared this with my boss so I can post a sample project.

              You can find the project here:

              http://sprend.com/download.jsp?fileid=7jQuyLrMxUKZ2fhkBYci

              I have rendered two wmv samples in the "out" folder where you clearly see that the processed version is out of sync. However it is perfectly in sync when you ram-preview it in the project.

              Thank you for taking your time to look a this

              / Olle