| Symptom | Cause and fix |
|---|
| No sound on a screen | Nobody clicked Start Display on it. Reload the screen link and click once. For a machine paired by QR code, tap it once; Live Control's warning goes away when the sound is on. |
| Pair a display: the camera will not start | The browser needs camera permission for the site. Or scan the code with your phone's camera app, or type the six characters. |
| Sound on one screen only | Music tab → Plays on. That screen is unticked. |
| Music stops during a presentation | Working as configured: Auto-mute includes Presentation. Untick it in the Music tab. |
| Music paused and nobody paused it | Check the transport: someone may have hit Mute or Pause from /remote. |
| Upload seems to do nothing | Watch the progress bar; on failure it turns red and shows the server's reason. Very large files simply take time. |
| Converted deck looks wrong | Replace file with a PDF, or replace the single bad slide with a PNG. |
| Screen shows the wrong meeting name | Settings are meeting-wide and push instantly; if one screen is stale, its socket dropped: it reconnects on its own within seconds. |
| Screen link says "Wrong or missing screen token" | The token was rotated. Copy the current link from Screens & Links. |
| Live share never connects | If the presenter is off-site, the LAN-only default blocks them: set DM_LAN_ONLY=0 or a TURN relay. See Live screen share. Fall back to HDMI. |
| Signed out unexpectedly | Should no longer happen across restarts. If it does, the browser dropped the cookie: sign in again; sessions last 7 days. |
| WebGL screensaver stutters | The room machine is too weak for that scene. Switch to a CSS backdrop. |