It's hard to tell remotely but my guess is a network problem between the streaming PC and the Centova Cast server.
If you are using ADSL or similar as the connection I would wonder if something else running (either on the streaming computer or elsewhere on the same network) is flooding the uplink (outgoing connection) so your stream suffers packet loss.
You could try a different encoder (for example Broadcast Using This Tool - B.U.T.T. https://sourceforge.net/projects/butt/ ) and see if that helps (you may need some kind of "loop" for your audio to use B.U.T.T.).
I would also try a ping monitor. I use "Ping Monitor" on my iPhone but the first Google result I got was https://emcosoftware.com/ping-monitor which looks worth a try.
Ideally you would run that on a separate device on the same connection and use your streaming server as the target,
One other possible cause would be a troublesome sound card driver (if you are taking a mixer input). I've seen the PlayIt Live streamer stop if the sound card plays up.
Anyone know why we have random disconnections from Playit live to Centova Cast. It occurs at random times.
Playit live streaming ( encoder) shows on break in streaming
Centova Cast - when disconnected shows streaming server 'online and operational' but " no current active source'
I have changed the server 3 times, and ceased auto updates on computer.