NetWorker EBR backup error "Internal Cycle Error"

Recently, there was a maintenance done in the VM environment.  All the EBR backup failed.  After rebooting the EBR appliance, we still experience intermittent issue with EBR backup.  Random VM backup failed with error " INTERNAL CYCLE ERROR: backstreamdir failed"

Working with support and eventually find out time is not in sync.  From the logs, they find out start time from NetWorker jobs seem to be about 10s off when other logs are checked from VM and EBR side.  We find out from our VM team time sync is turned off in VMtools for some reason and it should be disabled.  Because our NetWorker server and SN is not in domain, it is pointed to different NTP for time sync.  After confirming time sync issue is fixed, we don't experience any more issue.

So, always go from basic to troubleshoot VM backup like the past, are VMtools up-to-date?  ESX servers running the same version in the VM cluster?  Time is in sync?