Software-level volume control for OSX? For logistical reasons, my current sound configuration is the following.
          USB-C            3.5mm
Macbook ————————➜ Monitor ———————➜ Speaker

While this configuration works well, there's no way to change the volume of the computer without changing the physical dials of the speaker.

Is there any way to set the volume by &quot;software&quot; instead of using the outputs controls?
I use an app called Sound Control, which allows you to configure sound settings in all sorts of ways, including individually for each app.
I use it to provide software volume for my Aggregate Output device, which is a Dell Soundbar and my Thunderbolt Display together as one.
It may work for your setup.