I've been working on a music video for about a week and a half, doing most of my editing in AE (lot of green screen and motion graphics). I just exported a new mix of the song I'm using and then changed the reference files so AE would be pulling from the new track, rather than the old one. Now I'm getting a strange error where the audio is slowed waaaaaaaaay down in render previews while all the video plays at the proper speed. Any idea what the cause could be? I've never encountered this issue before.
Also strange, the audio and video still to begin at the same point in the render preview, but playback at different speeds, so it's in sync for that first frame or so, but then progressively drifts out of sync.
The two tracks were exported with the same settings, so I don't know why I would only be getting this issue now.
Using CS5.5. Song is a m4a file bounced from Logic Pro X.
Composition is 1080p 29.97
After effects can have issues dealing with compressed audio (m4a, mp3). Generally best to avoid it. Try using the WAV format instead.
I’ve found that WAV behaves much better in AE although one can still get very slight cumulative sync issues with RAM previewing over longer playback durations.
So far the only work around I’ve found, to check if things actually line up or not (with WAV files), is to do a RAM preview which starts a second or so before the point of interest. This prevents any noticeable sync issue building up.
I suspect the reason for this may be to do with a bad audio card or audio drivers. I would be curious to hear any other experiences, fixes or work-arounds on this matter.
Graham Macfarlane - CGI specialist
Elyarch Ltd - London UK
3D Studio Max | Vray | Pflow | PhoenixFD | After effects | Mocha