Found the solution. On the camera Setup page: Network -> Onvif -> Enable RTSP and set port (default 554). Sighthound: Foscam (Other H264) and reference the RTSP port defined on the camera.
I have several Foscam camera models, some of which are listed in the program and other use the Foscam Other H264 without problem. But I can not figure out the right settings for the FI9800P. Any help is much appreciated.