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I don't think there's an app around that lets you do this. One way to quickly change the audio output is to have the Sound icon in the menu bar. If you click it whilst holding 'alt' it will give you a list of possible outputs/inputs and you can choose the one you want.

You can further this by setting some Automator or AppleScript applications that you assign to a keyboard shortcut.
 
I don't think there's an app around that lets you do this. One way to quickly change the audio output is to have the Sound icon in the menu bar. If you click it whilst holding 'alt' it will give you a list of possible outputs/inputs and you can choose the one you want.

You can further this by setting some Automator or AppleScript applications that you assign to a keyboard shortcut.

It is possible.

I found this, but it only works with Google Chrome
 
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