Help with HIKVision DS-7608NI-K2/8P camera

[dbrewood]

Okay details:
The NVR is IP address 192.168.1.77
The Drive Camera is 192.168.254.5 (on the NVR network)
The Drive Camera virtual machine port is 65001
The router has a static route sending all traffic for 192.168.254.5 to 192.168.1.77
Ports 554 and 65001-65003 are open on the NAS firewall

Using the Surveillance Station on my Synology NAS (DS918+)I can connect to the camera as (i.e via the NVR and VM port):

So far trying to get FFmpeg working I've tried rtsp parameters of:

rtsp://192.168.1.77:554/Streaming/Channels/101 rtsp://192.168.1.77:554/Streaming/Channels/101/ rtsp://192.168.1.77:65001/Streaming/Channels/101/ rtsp://192.168.254.5:554/Streaming/Channels/101 rtsp://192.168.254.5:554/Streaming/Channels/101/ rtsp://192.168.254.5/Streaming/Channels/101 rtsp://192.168.254.5/Streaming/Channels/101/ rtsp://admin:[[email protected]](mailto:[email protected]):554 rtsp://admin:[[email protected]](mailto:[email protected]):554/Streaming/Channels/102/ rtsp://admin:[[email protected]](mailto:[email protected])/ISAPI/Streaming/channels/101/HighResolutionVideo rtsp://admin:[[email protected]](mailto:[email protected])/Streaming/Channels/101 rtsp://admin:[[email protected]](mailto:[email protected]):554 rtsp://admin:[[email protected]](mailto:[email protected]):554/Streaming/Channels/101 rtsp://admin:[[email protected]](mailto:[email protected]):554/Streaming/Channels/101/ rtsp://admin:[[email protected]](mailto:[email protected]):554/Streaming/Channels/102 rtsp://admin:[[email protected]](mailto:[email protected]):554/Streaming/Channels/102/ rtsp://admin:[[email protected]](mailto:[email protected])/ISAPI/Streaming/channels/101/HighResolutionVideo rtsp://admin:[[email protected]](mailto:[email protected])/Streaming/Channels/101 rtsp://admin:[[email protected]](mailto:[email protected])/Streaming/Channels/101/ rtsp://admin:password@http://192.168.1.77:65001/Streaming/Channels/102 rtsp://admin:password@http://192.168.1.77:65001/Streaming/Channels/102/ rtsp://camuser:[[email protected]](mailto:[email protected]):554/Streaming/Channels/101/ rtsp://camuser:[[email protected]](mailto:[email protected]):65001 rtsp://camuser:[[email protected]](mailto:[email protected]):65001/Streaming/Channels/101/ rtsp://camuser:[[email protected]](mailto:[email protected]):554/Streaming/Channels/101 rtsp://camuser:[[email protected]](mailto:[email protected]):554/Streaming/Channels/101/ rtsp://camuser:password@http://192.168.1.77:65001/Streaming/Channels/101/ rtsp://camuser:password@http://192.168.1.77:65001/Streaming/Channels/102/ rtsp://http://192.168.1.77:65001/Streaming/Channels/101 rtsp://http://192.168.1.77:65001/Streaming/Channels/101/

Which is every combination I can think of - hitting the camera directly or via the NVR with either the RTSP port or the virtual machine port. Typically, I get error:

[Camera FFmpeg] [Drive Cam FFmpeg] FFmpeg exited with code: 1 and signal: null (Error)

Which almost sounds like it's not connecting to the camera. Have I missed the obvious somewhere? Any help would be very much appreciated. This is driving me nuts....