I'm using After Effects CS3, and having trouble getting audio to play when using RAM Preview when I nest a composition with audio, inside another composition.
For example, if I make a composition and place an audio file inside, both scrubbing and RAM preview work. I'm able to hear the audio fine. But if I place that composition with the audio inside another composition, the audio when using RAM Preview no longer works. I can still scrub and hear the audio and when I export my movie the audio exports fine, but I'm not able to do a RAM preview with audio. Anyone know how to fix this or is this just not possible in AE CS3? Thanks!
If you're using any kind of compressed audio -- mp3, ac3, etc. -- you need to convert it to either an aiff or wav file. You can't use AE to do the conversion; find something else.
And don't forget that a movie's audio track can also be compressed. In fact, a movie can be compressed the totally wrong way for AE, rendering it almost useless. Read on:
Dave's Stock Answer #1:
If the footage you imported into AE is any kind of the following -- footage in an HDV acquisition codec, MPEG1, MPEG2, mp4, m2t, H.261 or H.264 -- you need to convert it to a different codec.
These kinds of footage use temporal, or interframe compression. They have keyframes at regular intervals, containing complete frame information. However, the frames in between do NOT have complete information. Interframe codecs toss out duplicated information.
In order to maintain peak rendering efficiency, AE needs complete information for each and every frame. But because these kinds of footage contain only partial information, AE freaks out, resulting in a wide variety of problems.
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