I have inserted in a joomla 1.7.3 article the following codes

{mp4remote}dl.dropbox.com/u/18404021/Video/Documentari/Life/Plants2.mp4{/mp4remote}
{mp4remote}hdwebplayer.com/player/videos/300.mp4{/mp4remote}

the first video starts only if the entire stream is cached.
The second video start after some seconds of caching.

I have this problem with Firefox and Opera. Chrome works well.

Is it possible the problem is inside the video? There is some information to insert into the video to mark it as a streaming video?

Solved,
the problem was about the atom moov at the end of the encoded file Plants2.mp4 that was not played correctly.

Here it is an article that describe what is the atom moov:
www.adobe.com/devnet/video/articles/mp4_movie_atom.html#articlecontentAdobe_numberedheader_0

Now I'm removing the above files.
Best regards,

Francesco