PsstTalk to your AI.
Hear nothing else
Psst is a free menu bar app for macOS. Hold space in Claude Code, start ChatGPT voice or dictate into Cursor: the moment your microphone turns on, every other app goes quiet. Let go, and your music is back.
Works with whatever is listening
Psst does not plug into your AI tools. It asks macOS which process is recording from the microphone, so it works the same for a terminal, an editor, a browser tab or a dictation app.
- Claude Code
/voice: hold space, talk, let go. Terminal or VS Code extension. - ChatGPT voice in the Mac app or the browser, and Claude's voice mode.
- Cursor, VS Code, Zed with their own dictation or an extension.
- Dictation apps such as Wispr Flow, Superwhisper, MacWhisper or Apple Dictation.
Tested on our Macs
Dictation in VS Code and Slack huddles. Everything else that records through macOS works the same way; if something does not, tell us.
How it works
- Your microphone turns on
You hold space in Claude Code, open ChatGPT voice or start a dictation. Psst notices within a tenth of a second and mutes every other app.
- Calls stay audible
An app that records and plays at the same time is a call: Slack huddle, Teams, Zoom, FaceTime, Meet in a browser. That app keeps its sound. Everything else goes quiet. How Psst tells a call from dictation.
- You stop talking
Half a second after the microphone goes off, the sound comes back exactly where it was. Your music kept playing where it was, and the volume never moved.
The menu bar tells you what is happening
Click the mark for the menu: switch Psst off for a while, decide whether calls stay audible, start at login, show the log.
For the curious: how it mutes
Psst creates a Core Audio process tap over every process except a call, with its mute behaviour set to muted. While the tap exists, those processes do not reach your speakers. When the microphone goes quiet, Psst destroys the tap and the sound continues where it was.
let tap = CATapDescription(
stereoGlobalTapButExcludeProcesses: callers)
tap.isPrivate = true
tap.muteBehavior = .muted
AudioHardwareCreateProcessTap(tap, &tapID)Who is recording comes from kAudioProcessPropertyIsRunningInput, polled ten times a second. One Swift file, Apple frameworks only, no network code.
Why not the volume or media keys
A play/pause key toggles and can start music you paused yourself. System volume silences your call along with the music, and many USB DACs ignore it. A tap avoids all three.
What Psst never does
- It never records. The mute works through a Core Audio process tap. Psst tells the tap to mute and reads nothing from it.
- It never touches your volume or media keys. Paused music stays paused. USB DACs and interfaces that macOS cannot control work the same as built-in speakers. Why Psst mutes instead of pausing.
- It never goes online. No network code, no account, no analytics, no update check. The version you download is the version you run.
- No third-party code. Apple frameworks only: AppKit, Core Audio, Service Management. One Swift file, which will be published as a public repository.
- No Dock icon, no window. Psst lives in the menu bar and in a small log file you can read any time.
- No app list to maintain. macOS reports which process records and which one plays. Psst works from that, so new apps need no update.
Install
- Download and unzip
You get Psst.app, under one megabyte. Move it to your Applications folder and open it.
- Allow “System Audio Recording”
macOS asks once. Psst needs it because muting happens through the same mechanism macOS uses to record system audio, even though Psst never records. If you clicked “Don’t allow”, the menu offers a shortcut to the setting.
- Start at login
Optional. In the menu, tick “Start at Login” and Psst is there every time, without a Dock icon.
Requirements
- macOS 14.2 Sonoma or later. Process taps do not exist before that.
- Apple Silicon or Intel, one universal download.
Questions
Does Psst work with Claude Code /voice?
Yes. Claude Code records through your terminal or VS Code while you hold space. Psst sees that process open the microphone and mutes everything else until you let go. Nothing to install in Claude Code. More on Claude Code voice.
Why does Psst ask for “System Audio Recording”?
Psst mutes through a Core Audio process tap, the same mechanism macOS uses to record system audio. macOS therefore files the permission under System Audio Recording. Psst never reads, records or stores any audio; the tap is only told to mute.
Which apps count as a call?
Any app that records from the microphone and plays sound at the same time: Slack huddles, Teams, Zoom, FaceTime, Google Meet in a browser. That app stays audible, everything else is muted. Dictation only records, so everything is muted. If you would rather have calls muted too, untick “Keep calls audible” in the menu.
Does Psst work with a USB DAC or an audio interface?
Yes. Psst does not change the volume and never presses media keys. It mutes the apps themselves, so it works with output devices macOS cannot control, and paused music stays paused.
Does Psst run on Intel Macs?
Yes. Psst is a universal app for Apple Silicon and Intel Macs running macOS 14.2 or later, which is the first version with process taps.
Does Psst send anything anywhere?
No. Psst has no network code, no account, no analytics and no third-party libraries. It is built with Apple frameworks only.
Can I keep one app from triggering Psst?
Yes. Put its bundle identifier, one per line, into the file exclusions in ~/Library/Application Support/Psst/. Those apps may use the microphone without muting anything.
Something isn't working. Who do I tell?
Write to info@createbetter.design. If you can, attach the last lines of the log: open the Psst menu and choose “Show Log”. It says which app used the microphone and whether muting worked, nothing else.
Does it cost anything?
No. Psst is free, now and later.
Psst 1.2 for macOS
Mutes everything while you talk. Keeps calls audible. Free.
The download goes up here once Apple has notarised the build, so macOS opens it without a warning. Want to hear when it’s out? Write us one line.
Tell me when it’s out