PsstPsst / Calls
Your call stays audible. Everything else goes quiet.
You join a huddle with a playlist running and a video paused in a tab you forgot. Psst mutes the playlist, the tab and the mail sounds, and leaves the people you are talking to exactly as loud as they were.
Short answer: An app that records from your microphone and plays sound at the same time is a call. Psst mutes every other app and leaves that one alone. When only recording happens, it is dictation, and everything is muted.
How Psst tells a call from dictation
| What macOS reports | What it usually is | What Psst does |
|---|---|---|
| One app records, nothing of it plays | Dictation, a voice prompt, a voice memo | Mutes every other app |
| One app records and plays | A call in Slack, Teams, Zoom, FaceTime or Meet in a browser | Mutes every app except that one |
| Nothing records | Normal work | Nothing. Everything plays. |
Psst reads both flags for every audio process ten times a second and groups helper processes under their app. Slack, Teams, Chrome and VS Code split their audio across helpers, so “Slack is on a call” only shows up when the helpers are counted together.
What we tested
On 19 October 2026 Psst muted a Slack huddle by mistake. That is why the call detection exists. Since then we have tested it with a Slack huddle and with a small test program that records and plays at the same time; in both cases the call stayed audible and everything else was muted. Other call apps report themselves to macOS the same way. If one of them does not behave, tell us and include the log line.
What the menu bar shows
During a call the speech bubble in the menu bar is filled and has two small arcs in its corner. The first line of the menu names the app that stays audible, for example “Call in Slack stays audible - everything else muted”.
If you want calls muted too
Untick “Keep calls audible” in the Psst menu. Then every other app is muted while the microphone is on, the call included. Psst remembers the choice.
Why not just turn the volume down
Turning the system volume down silences the call with the music. Muting per app keeps them apart, and it works on USB DACs and audio interfaces whose volume macOS cannot set. More on that in mute or pause.