Audio out of sync?
Out of sync audio is a problem that happens to us all at one stage or another and is very confusing and annoying to say the least. Wave Agent from Sound Devices is a great application for Mac and PC that lets you edit a range of metadata and even time code metadata from your out of sync audio instantly. This also has other applications such as effects manipulation which will be explained later.
Incase you haven't already just download it here: Sound Devices Wave Agent. Then we can begin with solving any audio out of sync issues.
Click Image to enlarge.
This is the layout of wave agent where you can change lots of information. Solving drift issues and out of sync audio with frame rate differences from the video by simply dragging the clips you want to change into the white box at the top and select all and then change the frame rate to match your video clip.
Wave Agent covers frame rates of: 23.97 ND, 24 ND, 25 ND, 29.97 ND, 29.97 DF, 30 ND and 30 DF.
If you know your time code at the start of each clip is right then keep the box ticked for preserve time code and this will still keep the same time and just re-sample the file. This stops audio out of sync problems that stretch over a period of a video. Usually starting out in sync and slowly getting out of sync.
Also check your computer isn't just processing the video slowly or the audio.
For effects based work you can change the playback speed of files by changing the sample rate. To give and example you can slow down playback of a file recorded at 96 kHz to 48 kHz will make the take playback at half its originally recorded speed and pitch.
For more specific details of Wave Agent and how it could help you just have a glance over the user guide for Wave Agent
Hope this helps and if not get in touch :)