I have imported the pre-Osclasspoint upgrade database sql file, in a new database for testing.
And the multiple item stats records are there, so this is not something created by the latest Osclasspoint upgrade (from an OTHER release).
The issue was there, no idea how and when it was created, since i took the customer for the last year or so.
What i will do is delete all item stats records. He will loose the views count, but nothing else i can do for now. Many issues this site and little money for the hours i have spend.