Video and Audio out of sync

I downloaded a film but the picture quality was bad and audio was good so I downloaded a second file extrated the audio from the one and replaced the audio of the second file as I was a different language. When using DubIt or VirtualDubMob or NanDub and video and audio is out of sync. At the beginning it is fine but slowly gets out of sync.

How do I solve this and what software do I use.

Thanks in advance.
Tanksta