Screen recording has no audio — the microphone is silently off by default
You record your screen with ⌘+Shift+5, do your whole walkthrough, stop the recording, watch it back, and there's zero audio. Complete silence. You have to redo everything. The microphone was off the whole time and nobody warned you.
Why does this happen?
macOS defaults to recording the screen without microphone input enabled. This is likely for privacy reasons — you don't want apps accidentally capturing audio — but it's a brutal gotcha when you're recording a tutorial.
How to fix it
Before recording: press ⌘+Shift+5 to open the screenshot toolbar.
Click Options → under Microphone, select your input (Built-in Microphone or external mic).
macOS will remember this setting for future recordings.
Note: this only captures your mic input. To record system audio, you need a third-party tool like BlackHole or Loopback.
Discussion
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