Summary
Audit Trail may not properly function when you manually add a repository's audit log folder as an audit source if that repository already exists as a data source.
For example, you may encounter this situation when dealing with migrated audit logs. Consider the following scenario:
Audit Trail Reporting may be unable to correctly load the specified audit logs.
Workaround
If you have encountered the listed issue, remove the folder from the list of data sources for Audit Trail Reporting. Then move the migrated log files to a different folder before adding that folder as a data source.