Confluence logs are filled with " Error writing response"

Hello Experts,

We are running confluence on Linux server Redhat6 , confluence is running fine but we noticed CPU spikes more than 900%  daily ( 3 -4 times ) 

Further noticed from the logs, have seen repeated errors in the confluence log.

Confluence 6.15.2

Scroll viewport - 2.13.0

Error message:

ERROR [http-nio-8090-exec-17] [[Standalone].[localhost].[/].[default]] log Servlet.service() for servlet [default] in context with path [] threw exception
java.lang.RuntimeException: Error writing response.
at com.k15t.scroll.viewport.request.AbstractViewportRequestHandler.writeToResponse(AbstractViewportRequestHandler.java:94)
at com.k15t.scroll.viewport.request.AbstractViewportRequestHandler.writeHtmlToResponse(AbstractViewportRequestHandler.java:77)

Please advise

Cheers

Madhu