R12.1.3: View concurrent request Output/Log shows error Function ncrorou returned error code 1003

We are getting below error while viewing output or log for a concurrent request -

"An error occured while attempting to receive the output arguments of the remote procedure. Function ncrorou returned error code 1003. The Application File Server process may have exited abnormally. Please contact your system administrator." 

Steps to reproduce the issue-

1. run any concurrent request like 'Active Users'

2. View Log/Output

This issue is intermittent. It sometimes vanishes itself.

Our E-Business Suite version is R12.1.3

We have tried following solutions which resolves the issue temporarily -

1. run cmclean and bounce concurrent managers

2. relink FNDFS and FNDWRR

3. bounce entire application