video is buffered completely before playing?

[psifertex]

It looks like from the docs that buffertime should be specified to control how much buffering is done, and that it defaults to 10. Whether I leave it at the defaults or set to 1, my videos are always downloading entirely before playing, though when I serve the same video via HTML5 video tags, they buffer fine so I don't think there's anything about the codec that requires it.

I'm using code basically identical to the sample at the top of the documentation.txt file, except that I've changed file to http and source points to a URL. Any suggestions?