HTML5 Video Fails in IE9 RC but not IE9 Beta

I have project that relies heavily on video and leverages html5 video when available. This was working across all browsers up until the IE9 RC was released about a week ago! This is very frustrating!

The confusing thing is I am able to play videos when they are sourced from a different location than my domain but not when they are sourced from my domain. It is as if the path to the video is being distorted.

WORKING:

<video src="http://www.jplayer.org/video/m4v/Big_Buck_Bunny_Trailer_480x270_h264aac.m4v" controls="controls">
</video>

NOT WORKING

<video src="http://www.mysite.com/video/Big_Buck_Bunny_Trailer_480x270_h264aac.m4v" controls="controls">
</video> 

Please bear in mind that this is working in all HTML5 brow开发者_如何学Csers (even IE9 Beta) but not the very latest 'IE9 RC' release. And that all read/write permission have been set correctly.

To test this for yourself visit this link: http://thebeer.co/labs/video.html

You should find in IE9 RC that the first two videos don't load but the last does. And even more strangely is you visit the direct URLS of the videos in IE9 RC they will play. All three videos work in Chrome (for the time being as the haven't dropped the H.264 format yet).

Please help me out guys...

A Broken Man.

Can you check your web server configuration? It seems that wrong MIME type is being sent. If you go to IE9 Developer tools, click the Network tab, press Stop capturing and reload the page, you will see that the first two videos are sent as text/plain, which means that no content-type is specified for them, and the last two are sent as video/mp4. Chrome seems to handle it somehow, but it really doesn't have to.

You can see the same using Firebug HTTP headers sniffer. Yet, Firefox doesn't play any of the videos, probably due to h.264 codec.