Please give a try to 1.1.8, I hope it will also solve the problem on your end.
https://s3.eu-central-1.amazonaws.com/moonware/ncs-inst-x86.exe
https://s3.eu-central-1.amazonaws.com/moonware/ncs-inst-x64.exe
On my side artefacts were rare and I don’t have them at all anymore but I have just tested for a few hours. Normally they were happening at the begining when connecting or reconnecting sources or when the CPU or Network usage were high.
If you use the custom url dialog to connect your sources, ensure that you select RTSP_TCP, not Unknown or another mode.