This is an improved import of https://code.google.com/p/switchaudio-osx

• Audio channels toggling: specify -s parameter twice to toggle between them
• Auto change back of previous audio channel after some pause (todo)

• Download & install Soundflower
• Extract & copy SwitchAudioSource to your $PATH (compiled for Mavericks)

You can compile it by yourself, too (xcode command line tools needed):

$ ./make.sh

Bind it to your favourite hotkey to toggle between outputs:

$ SwitchAudioSource -s "Built-in Output" -s "Soundflower (2ch)"