I've been in a discussion about this over on the mac forum but I thought I'd give give it a go over here to see if anyone has any ideas.

I'm using ffmpegX version 0.0.9u on Mac 10.4.4. Quicktime 7.0.4 with AC3 codec installed.

When trying to encode either an MPEG or m2v/AC3 elementary stream into Divx (ffmpeg or mencoder engine) with MP3 sound produces an avi file with no sound. Trying to produce an Xvid file (ffmpeg or mencoder engine) produces a "ping" straight away with a file of Zero KB (i.e. no video or sound).

When the MPEG file is dropped on the source format window, ffmpegX recognises that there is AC3 sound present.

When trying with the m2v component, I manually add the AC3 sound file in the "add audio" under the audio tab. I've also tried "Invert mapping" and selecting different audio tracks.

The only way I've got this this to work so far is to convert to something like MPEG with MP2 first (in MPEGStreamclip) which ffmpegX then deals with correctly.

Any ideas?