Answers.Body: <p>I'm not sure why they are not lining up, perhaps there is some problem with the audio track near the beginning that is causing truncation at the start.  Unless you have meaningful information there, my suggestion would be to remove the silence at the end of the audio file (since it is clear when it goes perfectly silent) and then end align rather than start align.  It appears that would likely give you proper sync.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2014-12-19T09:14:20.573Z
Answers.Text: The situation is slightly more complex because I have many mov file that I have split from a single mov file. My goal is to merge the output audio files of any mov and have a linear sound.
Answers.UserDisplayName: Marco
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2014-12-18T14:46:41.563Z
Answers.LastActivityDate: 2014-12-18T14:46:41.563Z
Answers.UserDisplayName: AJ Henderson
Body: <p>I've extract audio from a mov file. The output (m4a) has the same length of the video, but it starts first.</p>
  
  <p><img src="https://i.sstatic.net/AcdR1.png" alt="Audacity"></p>
  
  <p>Starting first, audio has a silent space at the end. I tried many different audio/video converter(any video converter, avs, freemake) but the result it's always the same. Any suggestion?</p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2014-12-18T00:45:14.593Z
Comments.Text: What program did you use to extract the audio?
Comments.UserDisplayName: KC McLaughlin
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2014-12-18T07:34:02.857Z
Comments.Text: Any video converter
Comments.UserDisplayName: Marco
Tags: <video><audio><conversion>
Title: Audio extraction from video issue
UserDisplayName: Marco
ThreadText: # Audio extraction from video issue
  
  (Asked by: username_0 on 2014-12-17)
  
  I've extract audio from a mov file. The output (m4a) has the same length of the video, but it starts first.
  
  ![Audacity](https://i.sstatic.net/AcdR1.png)
  
  Starting first, audio has a silent space at the end. I tried many different audio/video converter(any video converter, avs, freemake) but the result it's always the same. Any suggestion?
  
  **Tags:** video, audio, conversion
  
  > **Comments:**
  > **username_1**: What program did you use to extract the audio?  
  > **username_0**: Any video converter  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_2 on 2014-12-18. Score: 1
  
  I'm not sure why they are not lining up, perhaps there is some problem with the audio track near the beginning that is causing truncation at the start. Unless you have meaningful information there, my suggestion would be to remove the silence at the end of the audio file (since it is clear when it goes perfectly silent) and then end align rather than start align. It appears that would likely give you proper sync.
  
  > **Comments:**
  > **username_0**: The situation is slightly more complex because I have many mov file that I have split from a single mov file. My goal is to merge the output audio files of any mov and have a linear sound.  
  
  ---
  
  