Remuxing MP4 with AC3 audio - What to Use?

[THRobinson]

Well, almost done ripping Kenny vs Spenny to my media server using Handbrake. 6 seasons worth, but hit a small snag.

Had a few issues with this series, and now on season 6 and discovered that 4 episodes have a problem with the audio where the left chanel is about 75% louder than the right.

I downloaded and used a free app called GoldWave which I was able to balance the channels out with, but, no save option for AC3, had to save as a WAV. Then download another program to convert the WAV to AC3@192kbps so it matches the rest of the series.

I was trying to use AVIdemux to replace the audio track with the new one, but, even though it lists AC3 as an option it blurts out the error that only AAC and Mpeg Audio is supported. Saw an old post about that suggesting to use a nightly build which I did but same issue.

MKVMerge works fine, audio syncs as well, but... MKV, I want the files to be MP4.

So... any suggestions that don't require reencoding the video? I don't want to alter the video at all, it's the right size/quality, I just need to swap the old AC3 track with the new. Or any ideas why AVIDemux is being a pain?

[El Heggunte]

You can remux with ffmpeg, OR mp4box, OR mp4creator, OR L-Smash.

All of the above support AC3 in MP4 since 1975

[THRobinson]

I'm trying to find something with a GUI since I always have problems with the command type apps. I did try MP4Muxer (you listed MP4Creator but links to MP4Muxer) and just not getting it to work at all. Seems a few people had probs as well given the comments.

MKVMerge is a great program, super simple... figured there'd be an MP4 version. Will try MP4Muxer again...

[THRobinson]

Hmm, not sure why failed to work before, but this time managed to get it to work (MP4Muxer) so... sigh, now gotta fix the audio on the rest of the tracks.

[Kerry56]

How about MyMp4BoxGUI? Oops, too late. You've already got it done.

[LigH.de]

If the converter is based on ffmpeg or mencoder, the MP4 container in return may be incomplete. Using tools based on MP4Box or L-SMASH are recommendable for a correct result.

A very prominent GUI for MP4Box is YAMB.