Mac audio distorts Thunderbolt interface at high volume

Servant of Cats wrote:

In this Apple Discussions thread, MartinR writes that "Individual volume control per app is not a feature of macOS … If you need individual volume controls there is a nice app called Sound Source that will do the job."

😃 I was reading this thread and was about to tell the OP about SoundSource when I saw that you quoted me.

FWIW I use Audio Hijack and Airfoil from Rogue Amoeba. They are excellent apps, well supported. I expect to add SoundSource and Loopback to my system sometime this year, just haven't had the need for them yet.

Here's a bit of interesting history - Rogue Amoeba even supported Soundflower for a few years after Cycling'74 abandoned it in 2014; they eventually passed it to the original author who has done some maintenance but it's Intel only and is officially deprecated.

goombot wrote:

Is there anyway to turn down the overall output signal of the Mac so that when I am at full volume the level is not distorting my interface?

The way you would turn down "the overall output signal of the Mac" would be to not run the Mac at "full volume." Just like the way that you would avoid damaging your speakers and/or ears might be to not run your home theater receiver with the volume turned up all the way to the highest possible level.

The overall volume control for the Mac is in System Settings > Sound, although you can also access it from your menu bar if you set System Settings > Control Center > Sound to "Always Show in Menu Bar." Or use the keys marked with speaker icons (F10 = mute/unmute, F11 = lower volume, F12 = increase volume on my keyboard).

Turn your Mac volume up or down - Apple Support

It doesn't seem like there is a way to adjust individual sources on the Mac even within the Audio Midi setup unless I'm missing something.

It looks to me like both the Music app and the TV app offer volume controls that operate in addition to the system one. Third-party games that have music and sound effects often provide sliders to let you adjust relative volumes of the two. This is all on a per-app basis and there is no requirement for any particular app to offer the feature.

Adjust the volume in Music on Mac - Apple Support

Control playback in the Apple TV app on Mac - Apple Support

In this Apple Discussions thread, MartinR writes that "Individual volume control per app is not a feature of macOS … If you need individual volume controls there is a nice app called Sound Source that will do the job." I have not used that app, but I have heard of Rogue Amoeba, which seems to specialize in assorted sound utilities for Macs.