It works fine in Opera ...
As I understand the tag, it’s a proprietary MS addition to HTML which Opera have decided also to implement, but as it seems to work by calling the WMP dll, it may be platform specific, i.e. Opera probably won’t play the sound unless it’s running on Windows.
Just to show that presentation and coding are entirely separate, I hacked the page about a bit so it is standards compliant and cross-browser compatible. Not too difficult ever for a bodger like me. You can see the result here.
My modified page uses a JavaScript to add either a or a tag according to the browser.
As Firefox is a web browser and not a media player, and not tied in to the OS, it requires a plug-in to play embedded music files. It won’t use WMP. A discussion of the issue here:
https://bugzilla.mozilla.org/show_bug.cgi?id=92110
An alternative version of the page which lanches the default media player if no plug-in is installed is here.
Strictly speaking, neither nor is standards compliant. The tag is part of the W3C standards, and both Firefox and Opera handle it OK. Needless to say, IE can’t. An example here.
