@ge
I have almost the exact environment and Raspberry Pi.
I am running MM version 2.33.0, but that should not matter IMHO.
Btw, have 8Gb, and you ?
vcgencmd get_config total_mem
Can you open the RTSP URL in VLC and then open Window - Media Information ?
Then the Codec Details tab and please provide the Codec, Video resolution and Frame rate information.
I have H.264, 2560x1440, 25.
And can you try to change the config to this (add 2 lines):
    windows: [
      {
        windowSize: { width: 990, height: 557 },
        windowPosition: { x: 471, y: 20 },
        rtspStreamOverTcp: true,
        noSound: true,
        streams: [
           'rtsp://admin:Camadmin@172.16.0.37:554/cam/realmonitor?channel=1&subtype=0'
                 ]
      }
    ]
From looks the RTSP URL you are using a Dahua cam, right ?
Maybe you can try subtype=1 ??
Or another channel perhaps.
I do not know the relation between channels and resolutions.
Try to find a lesser resolution to see if it makes it better.
Also good to know how many other applications are streaming, for example Synology Surveillance Station.