Search by ID

We have a few users reporting a recent change in behavior regarding search. In any list where they have the ID column visible in the view, they could previously enter the ID number of a record and it would only show that record. 

In the last few days this functionality has changed as the search either shows nothing or random records where the id value may exist. We now have to prefix the id with "ListItemID: x"

I have not seen anything in bulletins to say a change in behavior.

Dhiran