Student grade feedback is showing from different courses.
To see how many feedbacks are out of sync I run the following query:
On our installation I had more than 1000 records. I could not run a simple update to use one specific assignment id because the right one was interchanging.
I was trying to find the code where this could happened without luck. This make me think that it must be happening during the upgrade to the new question engine Moodle 2.3.1.