Blocked Call Audio

A browser plays sound only after the page has had a gesture of the reader's own. Joining a call is usually that gesture, but not always — a call rejoined without a click, or a browser stricter than most — and then the call is up and silent with nothing on screen saying why. Where that happens, a warning notice reads Your browser is keeping the call quiet until you allow its sound. with a Play sound button; pressing it is the gesture, and the call's sound starts.

How it works

LiveKit reports the refusal itself: a remote audio element that fails to play flips Room.canPlaybackAudio and emits RoomEvent.AudioPlaybackStatusChanged. useLiveKitStore keeps that as isAudioPlaybackBlocked, cleared on disconnect, and startAudio calls Room.startAudio() from inside the button's click.

Room.startAudio() unmutes every remote audio element as it calls play() on them, which would undo deafen, so the store lays isDeafened back over them straight after the call, before its playback settles. A reader deafened while the sound was blocked is still deafened once it plays, and still deafened if the browser refuses it again.

flowchart TD
    Attach["Remote audio element attached"] --> Play{"Browser allows playback?"}
    Play -->|Yes| Sound["Call audio plays"]
    Play -->|No| Blocked["AudioPlaybackStatusChanged(false) → isAudioPlaybackBlocked"]
    Blocked --> Notice["Notice with Play sound"]
    Notice -->|Press| Start["Room.startAudio()"]
    Start --> Deafen["setRemoteAudioMuted(isDeafened)"]
    Deafen --> Cleared["AudioPlaybackStatusChanged(true) → notice gone"]
    Cleared --> Sound

Where it shows

MessageContentCallAudioPlaybackNotice renders in three places, so it is on screen wherever the reader is in the call:

• The call view, above its controls — /calls/[id] and a room's call view alike.
• The picture-in-picture window, above its controls — a press there is a gesture for the page that opened it, whose document holds the audio elements.
• Under the room's call strip, while the call view is closed — the reader is reading messages with the call running beside them.

Key files