I bump into a freakish problem today.
There were some ascii data readers that sometimes was not running (randomly)
All was fine on source files.
I made a lot of different tests, and in one on them the data reader was alternatively running/failure
No infos in log files.No error messages. Nothing.
Then, digging into data reader settings and entities involved, I discovered one entity with items duplicated.
Fortunately it was a service entity with no cubes and selections related to it, so It was easy to clear/reload it
After this action, all seems back to normality.
Note: the involved entity is fed only through data reader, and no manual changes have ever been done (infact changing manually a code from entity panel may lead to items duplication).
Attached you can find the entity extraction.
Have someone of you ever found a similar behaviour?