A easy tool for replacing audio in a video file.
Two modes, simple and advanced.
A joint effort from:
Simon Millward (FFmpeg code and testing)
Sagi (FFmpeg code and testing + manual)
Helge Tjelta (GUI & programming)
Phil Pendelbury, Erik Guldager, Pål Svennevig (testers and helpers)
Att: You need to have FFmpeg installed on your computer for this tool to work.
In advanced mode, you can specify start, duration, codec and bitrate.
http://macappstore.org/ffmpeg/ for info about installing ffmpeg on mac.