as I understand it, there is a problem to NOT encode at least video.
To separate still have a demuxer, this quick, then, with the sound can do everything (but better without the time correction ;) ). Then tucked any coding by the encoder in the source format, then makerom gluing with the video, it's too fast, the video remains intact.
wyatt answered on July 8th 19 at 16:27
Using Adobe autdition You can do with sound is absolutely what you want. View a couple of video tutorials on YouTube and all will become clear. The program can add video files and work with their sound tracks.
Rollin_Osins answered on July 8th 19 at 16:29
Sony Vegas Pro is the most simple program for video editing