I dunno that angelic music really goes with some of the more violent scenes, reminds me of clockwork orange

Try this:

https://addons.mozilla.org/en-US/firefox/addon/stop-autoplay...

See also: http://kb.mozillazine.org/Muting_browser

Unfortunately flashblock and stop autoplay both prevent the viewer from starting at all, and once you click to start, it plays the unmutable music.

There's a Flashmute extension on there too, but it's windows-only.