If you search for "free volume mixer for Mac," you'll find one main result: Background Music. It's the only notable free, open-source per-app volume control app for macOS. Let's look at what you actually get — and what you give up.
Background Music: the free option
Background Music is a free, open-source app hosted on GitHub. It gives you:
- Per-app volume sliders — basic volume control for each running app
- Auto-pause music — pauses your music player when another app plays audio, resumes when it stops
- Default output device setting — override which device apps use by default
What Background Music doesn't have
- No volume boost past 100% — sliders go from 0% to 100% only. Can't amplify quiet apps.
- No volume profiles — can't save and switch between configurations
- No auto-ducking — auto-pause is different from auto-duck. Pause stops music entirely; ducking lowers it to a comfortable background level. Many people prefer quiet background music during calls over total silence.
- No volume memory — doesn't remember per-app volumes between restarts
- No keyboard shortcuts — no hotkey to toggle the mixer or mute all apps
- No output device switching — can't switch speakers/headphones from the same panel
The reliability problem
Background Music's biggest issue isn't features — it's stability. It works by installing a virtual audio device driver, and this driver breaks with macOS updates. After nearly every major macOS release (Ventura, Sonoma, Sequoia, Tahoe), users report:
- Virtual device fails to install
- Audio crackling and glitches
- Apps not being detected
- No audio output at all
- App crashes on launch
Since it's a volunteer-maintained open-source project, fixes aren't always timely. You might be without per-app volume for weeks after a macOS update.
Other "free" options
eqMac (free tier)
eqMac's free tier provides a system-wide equalizer but not per-app volume control. The per-app features require eqMac Pro (subscription). The free version is useful if you primarily need EQ, not volume mixing.
macOS built-in
macOS has no built-in volume mixer. The closest is the alert volume slider in System Settings → Sound, which only affects system sounds — not app audio.
When free is enough
Background Music might be fine if:
- You only need basic per-app volume (0-100%)
- You don't need profiles, auto-ducking, or volume boost
- You're comfortable fixing it when macOS updates break it
- You're okay with a virtual audio device in your audio chain
When it's worth paying
A paid volume mixer is worth it if you need:
- Reliability — works after macOS updates without waiting for volunteer fixes
- Volume boost to 200% — amplify quiet apps beyond their built-in maximum
- Profiles — save configurations and switch between Meeting/Focus/Gaming with one click
- Auto-ducking — automatic volume reduction during calls, not just auto-pause
- No system drivers — works with Apple's native API, no virtual audio devices that can break
SoundDial costs €14.99 — one time, not a subscription. For context, that's less than two months of a Spotify subscription, for a tool you'll use every day. It's less than half the price of SoundSource ($39), and includes features (profiles, auto-ducking) that SoundSource doesn't have.
Available on the Mac App Store — Apple-reviewed, sandboxed, no system drivers. €14.99 one-time, no subscription, macOS 14.2+.