▎ Setup:
▎ - Zoom Meeting SDK for Web, Component View (ZoomMtgEmbedded.createClient()), version 3.13.2.
▎ - Participants are view-only attendees (role 0) in a webinar scenario. They must hear the host but never speak — their microphone is never needed.
▎ - We init with client.init({ zoomAppRoot, patchJsMedia: true, … }) then client.join({…}) using a Meeting SDK signature (not Video SDK).
▎
▎ Problem:
▎ To start audio for these listen-only attendees we have two paths, both problematic:
▎ 1. client.getMediaStream().startAudio({ speakerOnly: true }) — getMediaStream() does not return a usable audio stream unless SharedArrayBuffer is available. Console shows:
▎ “Background noise suppression requires SharedArrayBuffer and is only supported on desktop browser”.
▎ 2. The toolbar “Join Audio” / Computer Audio button — this triggers a getUserMedia microphone permission prompt. Many viewers click Deny (privacy concerns), and then they
▎ cannot hear the host at all. Chrome remembers the denial, so the prompt never reappears and audio stays broken. This is causing real attendee drop-off.
▎
▎ To get SharedArrayBuffer we tried enabling cross-origin isolation: Cross-Origin-Opener-Policy: same-origin + Cross-Origin-Embedder-Policy: require-corp and credentialless. In
▎ both modes the SDK’s own cross-origin resources get blocked (ERR_BLOCKED_BY_RESPONSE, e.g. images from us06images.zoom.us), which breaks the embedded meeting — even in Chrome
▎ with credentialless.
▎
▎ Questions:
▎ 1. Is there a supported way to play meeting audio for a listen-only (role 0) participant without triggering a microphone permission prompt and without requiring
▎ SharedArrayBuffer / cross-origin isolation?
▎ 2. Is SharedArrayBuffer strictly required for startAudio({ speakerOnly: true })? Is there any way for getMediaStream().startAudio({speakerOnly:true}) to work without
▎ cross-origin isolation?
▎ 3. What is the official, complete COOP/COEP configuration that makes the Meeting SDK for Web fully functional under cross-origin isolation? Does the SDK support COEP:
▎ credentialless? If yes, which exact headers and which Zoom CDN/CORP requirements are needed so that us06images.zoom.us and worker/iframe resources are not blocked?
▎ 4. Is there an init/join option or meeting setting to join audio as receive-only / speaker-only automatically, bypassing the microphone entirely?
▎ 5. Does the latest Meeting SDK version improve non-SAB audio or COEP compatibility compared to 3.13.2? Which version do you recommend for this use case?
▎ 6. Is the microphone permission prompt for a receive-only attendee expected behavior, or a sign of misconfiguration on our side?
▎
▎ What we need: view-only webinar attendees should hear the speaker through their speakers with no microphone permission request on any browser (Chrome, Yandex, mobile, Safari).