You're streaming on Twitch from your Mac. OBS is capturing your game, your mic, and your desktop audio. But "desktop audio" is one mixed signal — your game, alert sounds, background music, Discord, and notification pings all land on the same channel at whatever volume macOS decides. Your viewers hear an unbalanced mess where alerts blast over gameplay, music drowns out your commentary, and a Slack ping randomly interrupts the stream.
Why streaming audio is hard on Mac
OBS captures "desktop audio" as a single mixed stream — everything playing on your Mac combined. On Windows, streamers use the built-in volume mixer to pre-balance apps before OBS captures them. On macOS, that mixer doesn't exist. Your pre-capture mix is whatever happens to be playing at whatever levels apps default to.
Professional Mac streamers typically use virtual audio routing tools to create separate audio channels for each source. That works, but it's complex to set up, requires audio drivers, and breaks when macOS updates change audio frameworks.
Pre-mixing with per-app volume
SoundDial lets you balance every app before OBS captures the combined output. Since OBS picks up the final mix, adjusting individual app volumes with SoundDial directly affects what your viewers hear.
Streaming profile
- Game: 60% — present but not overwhelming
- Alert app / Streamlabs: 40% — audible for viewer engagement, not louder than gameplay
- Music (Spotify / Apple Music): 15-20% — background vibes, DMCA-safe volume
- Discord: 50% — co-stream or mod communication
- Browser: muted — no surprise tab audio on stream
- Slack / Mail / Messages: muted — personal notifications stay off-stream
Quick adjustments mid-stream
Viewer says the game is too loud? Lower just the game's slider from the menu bar without alt-tabbing out of your stream scene. Music too quiet? Nudge it up. A quick slider drag in SoundDial is invisible to viewers — no on-screen settings panels, no stream interruption.
Auto-ducking for commentary
Enable auto-ducking to lower game and music audio when you speak. Your commentary always cuts through, and audio rises back up during quiet moments — exactly what professional streamers achieve with expensive audio routing setups.
Get SoundDial on the Mac App Store — €14.99 one-time purchase, no subscription, macOS 14.2+.