which VLC version you are using? try the PC version first.
you need to put the RTSP port in VLC if you are accessing it remotely
try the using VLC on local LAN first, and set the video resolution to lowest to see if it will work.
Sometimes VLC will hang or just do nothing if the video size is 1280
these are tried and tested on my end.
rtsp://192.168.0.xx:554/play1.sdp
rtsp://192.168.0.xx:554/play2.sdp
rtsp://192.168.0.xx:554/play3.sdp