Audio Device Swapping
tl;dr: For everyday audio device swapping, you probably want to use the macOS controls (Settings > Sound) rather than the dropdowns in Tuple's preferences. (You can do this quickly by Option-clicking the speaker icon in your menu bar.)
There is a potentially-confusing caveat when setting your audio device in Tuple's preferences.
Imagine you have your Airpods set as your output in the macOS Sound preferences.
Now, you override those settings in Tuple's preferences and choose Bose QCIIs as the output.
Now, your volume up, volume down, and mute keys on your keyboard will affect the Airpods, not the Bose QCIIs. This is because the keyboard controls always affect the System Default device (the one you've chosen in Sound preferences).
We provide the dropdowns in our preferences to support folks with complex audio setups, such as using tools like Krisp.