I have 2 VCDs of the same film in two different languages. Since the version in the language I don't understand has a much better picture, I want to remove the audio and replace it with the audio stream from the other VCD.

Both versions span two discs each, and one version is further split into 2 DAT files per disc. After merging each version into one full MPEG, I noticed the runtimes differ by 15 seconds. (I had to do some splicing to cut the redundant frames on the version which is split into 2 DAT files per disc).

If I mux the audio from VCD 1 with the video from VCD 2, I find that only the beginning and part of the middle is in sync, while in other scenes there is audio drift to different degrees. Thus, it seems like I will need to edit the audio scene by scene.

Is there a program which will allow me to merge audio and video while previewing the result to solve any potential sync/time delay issues?