Here's the original video, which I've opened in QuickTime Pro 7.
With QT Pro 7, I do a apple-J and get the properties of the file.
Since Flash is just another container, I can extract the video and audio.
So, select each track in turn and then click 'extract'. You'll get two new windows
The, do apple-A on the audio track to select it all. Switch to the new video window, and then select Edit > Add to Movie
Then save as self-contained movie, and you'll get a .mov instead of .flv
And here we are
For extra points, you can rename the .mov to .mp4 and it should play OK on most devices. The reason is that the mp4 container format is based on the QuickTime mov container.