Can you tell wich version of firefox you currently use?
I was able to do this with firefox 3.6 with the webm format.
Do you use firefox 4 or Minefield (http://nightly.mozilla.org).
I don't use the video tag anymore to avoid the upload of 3 differnent formats on my server.
If you are testing this stuff on localhost ("127.0.0.1") I suggest you to upload the test on a real server to see if you face the same issue.
This group is obviously dedicated to HTML5, so I will not tell here what I'm thinking about HTML5 .
Keep running Forest
I am using Firefox 18.104.22.168
try something like this:
<video src="showreel.mp4" controls width="420" height="236" >
<source src="showreel.mp4" type='video/mp4; codecs="avc1.42E01E, mp4a.40.2"' />
<source src="showreel.webm" type='video/webm; codecs="vp8,vorbis"' />
<source src="showreel.ogg" type='video/ogg; codecs="theora,vorbis"'/>
Of course all ur videos should be compress with the right codec...
I had the same problem and this solved in almost browsers... except for ie9... u know... still sucks....