Audio ducking settings in a screen recording workflow
Audio ducking — automatically lowering background or system audio when your microphone detects speech — sounds like a useful automation and is genuinely helpful in some recording contexts. In screen recordings specifically, it often produces exactly the wrong effect.
What ducking is designed to do
Ducking is designed for situations where continuous background audio (background music, ambient sound) should lower when a presenter speaks, then return when they stop — a behavior borrowed from broadcast production where it works well. In a controlled environment with clearly separated foreground speech and background music, it’s genuinely useful.
Where it goes wrong in a screen recording context
Screen recordings often include system audio — application sounds, notification pings, the audio track from software being demonstrated — that isn’t background music but is itself content. Ducking that system audio when you start narrating can make a demonstration of a video editor’s playback feature silently lower the audio being demonstrated the moment you start explaining it, which actively undermines the tutorial.
On macOS: check for system-level ducking, not just your recorder’s setting
macOS has a system-level audio ducking behavior that activates when Siri or certain accessibility features are enabled — this can cause unexpected audio lowering during a recording that has nothing to do with your recorder’s own settings, similar to the OS-level interference covered in our OS update troubleshooting guide.
When ducking is actually the right call for a screen recording
If your recording genuinely separates your narration from background content — a tutorial with background music you deliberately added, distinct from application sounds — ducking does the intended job cleanly. The issue is leaving it enabled by default when system audio is part of the content rather than just a background layer.
How to check: do a short test recording with system audio active
Recording a 30-second test clip while narrating over active application audio reveals immediately whether ducking is affecting the system audio — you’ll hear the application sound drop when you start speaking if ducking is active and configured broadly enough to catch it.
Frequently asked questions
Should I use audio ducking when recording screen recordings?
Usually not if your recording captures system audio — ducking can lower that system audio when you narrate, which removes sound that’s part of the content being demonstrated rather than just background noise.
Why does system audio get quieter when I start speaking in my recording?
Audio ducking is likely enabled — either in your recorder’s settings or at the OS level — and it’s lowering system audio in response to your microphone detecting speech.
Related reading: Getting internal audio right on Mac · Fixing audio sync issues in screen recordings · Your recording has a fan buzzing in the background