Modern browsers often block videos from autoplaying with sound. HeySummit's Start stream muted option helps pre-recorded videos and supported streams autoplay more reliably by starting playback muted, then letting attendees unmute it.
To find it, go to Content & Schedule > Sessions, open the session's Actions menu, choose Manage Session, and open the Broadcast tab. After selecting the broadcast type and provider, look under Playback options for Start stream muted.
Use this with the relevant autoplay setting when you want a video or stream to begin automatically. Autoplay still depends on the attendee's browser, device, and provider. If you leave Start stream muted off, a browser that blocks autoplay with sound may wait for the attendee to press play.