We have a very strange issue. Courses containing over a certain number of students (not sure exactly how many) have started having an issue when manually entering grades in the Gradebook. Faculty go to the Gradebook and turn editing on and then enter the scores for a particular assignment and then click update. They then find that the scores are saved for all but the last 3-4 students. No matter how many times you try to enter the scores and update they will not save. It is always the last three to four students whose scores do not save.
This does not happen if they create an assignment through the "Add an activity" interface and grade the activity on the Submissions page. This issue just started occurring at the end of last week and absolutely no changes have been made to the server, Moodle, or any modules. Prior to last week manually entering grades was working as normal. I am at a loss for what could be the reason for this to suddenly start happening. Any suggestions will be appreciated.