May I know specs of your hosting service, such as CPU (size and core) and RAM?
We never encountered error 508 with JNews before, so we need to investigate it further.
FYI, ERROR 508 means website is hitting one or more of the hosting account’s virtual resource limits: CPU Usage, RAM Usage, I/O usage or Entry Processes.
Could you ask your hosting provider to provide CPU usage log? I’m afraid there is other background process that caused high CPU usage.
Actually, a lot of our user using budget hosting service that running JNews without error. Even though this is clearly an server side issue, but we still need to investigate it further before blaming each side (hosting & theme) because different environment might need some adjustment.