MKV/AVI audio editing

[Skizzarz]

Hi there, I've been trying to search around on how to do this but I haven't been able to get all the information.

I have an HD video that's audio track is mono. I'd like to have the audio track as multi-channel.

I have the same video in lower quality with the multi-channel audio track. The video file is AVI, the HD video file is MKV.

I believe I can use MKVMerge but I haven't been successful.

How would I remove the mono-channel audio track from the MKV and insert the multi-channel track while not degrading any of the content I'm working with?

Thanks for any help!

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I'd found this: https://forum.videohelp.com/threads/286462-Any-way-to-change-audio-in-MKV-file?p=187615...=1#post1876159
but it's too open-ended for me.

[Baldrick]

With mkvmergegui (mmg.exe) can you remove and add audio tracks and save as a new mkv? What exactly does not work?

[Skizzarz]

I was able to remove the mono audio track, would I use the attach area to attach the new audio file?

[Skizzarz]

Alright, so I was able to get the multi-channel audio track in with the HD video, it was add/append I was looking for. For some reason the mp3 track doesn't play the same way it does between the HD and non-HD video. In the HD clip I added it to, it plays mostly out of the front 3 channels and treble is barely audible out of the surrounds, but in the original the mp3 track plays better and more fully in surround. I have ac3 filter along with Matroska splitter installed for playing MKVs back in Windows Media Center, may the ac3 filter be messing with the mix? I have it set to 3 fronts 2 rears + subwoofer.

[Skizzarz]

It's weird, the new file sounds fine in VLC but in Windows Media Center regardless of the speaker set-up being 2 or 5.1, it doesn't sound right, most of the sound is in the front 3 channels, anyone have any clue about that?

[davexnet]

If it's playing in WMP it's propbably using the Diresctshow chain. AS you mentioned, either ac3filter, or the ffdshow mixer may be doing something to the mix.

[Skizzarz]

cheers dave, I'll muck around with ac3filter.