I use a Sony HDR SR11 video camera which creates an mpeg2 muxed file. Which means the video and audio are combined into one signal. Muxing, or “multiplexing”, can mean slightly different things for video processing and digital broadcasting, but it basically refers to the combining, by some process, of the audio and video streams.

Once they’re combined, they must be taken apart again in order to edited or altered separately. They must be demuxed.

I got no audio when I imported these muxed files into Premiere Pro until I discovered MPEG Streamclip, “a powerful free video converter, player, editor for Mac and Windows. It can play many movie files, not only MPEGs; it can convert MPEG files between muxed/demuxed formats for authoring; it can encode movies to many formats, including iPod; it can cut, trim and join movies. MPEG Streamclip can also download videos from YouTube and Google by entering the page URL.”