Yay, I think I just set up things so that my computer automatically changes from the normal audio output to the virtual device that pipes audio to both the normal output and the streaming program when I start the streaming program, and then undoes that when I quit it.
This was more of a pain in the ass than it should be as the only way to change this via Applescript seems to be to launch the Control Panel and *grovel through the list of its UI controls*. And of course these scripts needed to be allowed to control the UI, and this allowance doesn't like to stick...
(I did this all by creating a new context in ControlPlane, which is an incredibly useful app for making shit happen automatically when your environment changes.)
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