This MIDI file is Samuel Barber's "Adagio for Strings."
As you can see, there are controls for starting and stopping the MIDI file, saving a copy, and using the MIDI Manager instead of QuickTime if you want. Also, if you click on the little QuickTime icon in the top left corner of the plug-in, the registration dialog appears. This is where you enter your name and code to register "QT MIDI Plugin." There is also a blue arrow on the left of the "Status:" part of the plugin. This tells you that this particular MIDI file will not loop around repeatedly playing itself over and over. If you wanted a MIDI file to loop indefinitely, use the "LOOP=TRUE" tag in your web page. In that case, the blue arrow would show itself looping around.
If you hold down the option key while the mouse is over the plug-in, you will see that it turns into a hyper-link. Clicking on the plug-in with the option key held down will take you to my web site, where you can get updates for "QT MIDI Plugin" and see if there's any new stuff available!
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