Volumizer

Volumizer gives you the volume mixer it's always been missing, control volume for every app independently.
  
PER-APP VOLUME CONTROL
Adjust volume and mute for each running application separately. Turn it down without touching anything else.

10-BAND EQUALIZER   
Fine-tune audio per app with a built-in 10-band EQ. Choose from presets like Bass Boost, Vocal, Rock, and more or dial in your own.

OUTPUT ROUTING
Send different apps to different speakers. Music to your desk speakers, calls to your headphones all at once.
  
OUTPUT GROUPS
Combine multiple devices into one output group and play audio through all of them simultaneously, with independent volume per device.

FOCUS AUDIO
Automatically duck background apps when you switch focus. The app you're using plays at full volume while everything else quiets down.

CUSTOM KEYBOARD SHORTCUTS
Control system volume with configurable global hotkeys. Works from any app.

PRIVACY-FIRST
No kernel extensions. No audio drivers. Requires only Screen & System Audio Recording permission.

Start with a 3-day free trial, then $0.99/month to unlock EQ, output routing, output groups, and Focus Audio. Per-app volume control is free.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/