Is there a good program to join .avi video & .avi audio together as 1 file?

I can’t find anything. 21 SOA episodes I’ve downloaded are .mkv so I had to use .MKV Cleaver to turn them into .avi to use them for my Sony Vegas program, but the audio and video are split and it’s driving me crazy.
I’ve already tried emailing the original uploader to see if he’d be willing to reup the .avi files of the ones I need, but no response.
Help!
Answer #1
u can just use avimux>
http://www.videohelp.com/software/AVIMux-GUI
though depending on the mkv files’ formats it might not work, in that case u have to use mkvmerge to create mkv(with different audio??) then re-encode to avi using a converter.
u can also use mp4 muxing tools (for updated video formats which arent supported by avi container) {u can import mp4 in sony vegas too}
http://www.videohelp.com/software/My-MP4Box-GUI
Answer #2
avidemux can convert the container from MKV to MP4 or AVI in seconds, without splitting the video & audio streams
avi is a container format
in the newest avidemux use MP4v2 or AVI as output format with both streams set to “copy”
Answer #3
AVS4you Video Converter should convert the mkv to avi as 1 file. At least it has for me in the past but I haven’t used it in awhile since I built my HTPC with Plex.
As far as joining the 2 files, I honestly don’t know if AVS4you converter would do that or if you would need their Video Editor instead.
Answer #4
You could check these out too..
https://www.iskysoft.com/video-editing/combine-audio-and-video.html
The Filmora editor mentioned..
https://www..org/viewtopic.php?t=23374975&highlight=
Have fun !
Answer #5
I use xmedia recode to change mkv to other formats. For me its mp4 for the xbox360 that I stream to. It does it in seconds too.