[qqwref]

Originally Posted by G.S.M

go to your computers volume on the taskbar and you can turn off plugin-container (firefox) if you have something open in your browser that utilizes plugin-container, otherwise it won't show up.

you can play without muting your entire computer... just your browser!

That would be useful, but:

Originally Posted by qqwref

Given that I have XP and use a standalone, I don't see any other way to get this effect.

You can't turn off the sound of individual programs in XP, and standalones don't play in the browser.