I'm using Windows 7 and when I open the sound mixer, 3 applications show up: system, plugin container for firefox, and digital audio. I can click on 2 of these 3 no problem and go to a configuration page where I'm able to direct the sound to 1 of my 2 sound cards... but the plugin container does nothing when I click on it. I want to direct the audio from a streaming podcast that's coming through plugin container to the usb headset temporarily... Googling suggests the simplest answer is to just use another browser or disable the plugin, but I'm stubborn and love firefox so I hope you can help! :)