I tried "Lionel Hampton How High The Moon" I found on YouTube maybe the same one.
I used Youtube Downloader HD both for normal .flv & .avi .The video results were odd.That may be why the video didn't work for you.
Youtube Downloader HD .flv = 87.7 Kbps, 320*240 (4/3), at 29.970 fps, Sorenson H263
Youtube Downloader HD .avi = 50.7 Kbps, 320*240 (4/3), at 29.917 fps, xvid
IE TIF .flv = 213 Kbps, 640*480 (4/3), at 29.973 fps .
The regular YouTube Downloader didn't work on this one.