Streaming non-mp3 audio files?

My current web host does not allow mp3 files and I would prefer to keep all my files in one place, rather than storing mp3s on an external file hosting service.

What other formats can be streamed in Flash? I was pretty sure .swf and .flv sound files would work, but they aren’t - unless I’m doing something wrong.

Here’s the basic code I’m using:

private var _song:Sound;
private var _songFile:String; 

then in an event handler:

_songFile = _songNameField.text;
_song = new Sound();
var soundFile:URLRequest = new URLRequest(_songFile);
_song.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler);
_song.addEventListener(SecurityErrorEvent.SECURITY_ERROR, errorHandler);

I don’t see a message from either of my error handlers, just no sound. The sog.swf file itself works.