Firefox, you have let me down.....

[MuGen]

Well I actually had to re-install QuickTime and when I did it asked me to do the MIME settings so that it knows which files to handle when serving the internet.

But open up QuickTime, and go to Edit ---> Preferences ---> QuickTime Settings

There should be a pulldown box, click it and Select 'Browser Plugins'

Click on the button that says MIME Settings and make sure you have a checkmark on these file mime types:

Streaming video
Video - Video only or video with sound formats
Audio - Audio only file formats
MPEG - MPEG system, video, and audio files.