I have developed an HTML5 audio widget for use with EDT and it seems to be working pretty well. I'm hosting a sample application that uses the widget at the following address, so please go and have a look.
On the site you can find a link to download a project that includes the new widget and also the sample application, which should give you a pretty good idea of how you can use the widget. I am making the widget freely available.
I'm keen to wheedle out any browser compatibility issues so please let me know if you run in to any such issues.