I have two separate monitors: one at my desk in my recording studio and the other in my sound booth. Both monitors are connected to my MacPro, so my wireless keyboard and trackpad can travel with me to either location. The problem is each time I change locations I also have to go to System Preferences and change the Sound Output source so I can hear the audio. I have found "OPEN>Open a System Preference Pane" in KM, but how to continue the macro to choose the correct audio output from the "Select a device for sound output"? When the Sound Output window opens, the menu doesn't seem to be active, thereby necessitating the use of the trackpad (which I am trying to avoid).
This might be achievable using Move and Click at the Center of the Found Image.
What I personally use is the Rogue Amoeba app SoundSource. It includes Shortcuts actions for changing the Audio Output Device and you can execute these from KM. I combine this with some additional actions to select an AU equaliser preset specific to each set of monitors / headphones.
Upvote for @PatTheDog and @ccstone recommendations. I use SoundSource for quite a few things and while it is an investment, it is a very powerful tool and had macOS Shortcuts compatibility which means it also works with Keyboard Maestro 10 via the Execute a Shortcut action.
I also use SwitchAudioSource CLI for a lot of things. The nice thing about it is it’s free. Thus I recommend trying it first, because I am 99.9% certain it can do whatever you need. But SoundSource also has a free trial so you might as well check it out too.