“Synthetic cam” appears instead of my webcam
If the browser's camera permission is denied — or the prompt sits unanswered for ten seconds — VirtualCam falls back to an animated test pattern so the session still works.
To use your real camera, click the camera icon in the browser address bar, allow access, and refresh.
The output pane never shows a frame
Video travels over WebRTC, which needs outbound UDP to reach the GPU. Strict corporate firewalls and some VPNs block it, and there is no slower fallback path - if the connection can't be made, the stage says so instead of showing output.
Try turning off the VPN, or switching to a different network (a phone hotspot is a quick test), then reload the page. The status chip in the stage reads "WebRTC" once video is actually flowing.
The session ended on its own
Two common causes: the daily streaming limit was reached (check Settings → Usage), or the GPU worker was interrupted - rare, but cloud GPUs occasionally fail. Start a new session; your personas are unaffected.