I use VLC too, it can take a while to initiate the stream sometimes.
Once you've opened the stream (in my case, opening rtsp://192.168.0.135:9000/live via Media > Open Network Stream > enter a network URL) you can then create desktop shortcuts to each stream via Media > Save Playlist to File for easier access:
For Fisheye camera streams, you may want to dewarp the stream with a post-processing method before streaming it to VLC - the method is detailed in this community post, except they are using FFPLAY there instead of VLC.
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