RTSP black screen troubleshooting: what to check when VLC works but your VMS does not (opens in new tab)

An IP camera stream failure is rarely just “RTSP does not work”. The useful question is more specific: Did RTSP authentication succeed? Did DESCRIBE return the SDP you expected? Did SETUP choose TCP interleaved or UDP RTP? Is media arriving after PLAY? Are RTP sequence numbers continuous? Does the codec profile match what the client can decode? Is ONVIF handing the VMS a different URI than the one you tested in VLC? When a camera plays in VLC but not in an NVR/VMS, the failure is usually in t...