Repeats in search results and page number issues.

Since update to 5.3.0, I have noticed that searching the image gallery often shows repeats of the same image among the search results.
Anyone else seen this?

I am having a hard time reproducing it at the moment as results change, but here is a simple example. I searched our reference photos for 'pie'.
There are 16 results shown including one repeat. The first time I did this search, there were three repeated images. They are repeats not copies on the database - the duplicates have the same image ids.

The page jumper shows 1/12054. 12054 is the total number of image pages on our site. The actual number of search result pages is 2.
My screen shots show that the last image on the first page is repeated on the second page.
There is a 'next' arrow on page 2, but there isn't a page 3 - you get a blank page if you go to next.

updated by @lornawebber: 07/03/16 03:00:54PM

Here's another, example, where I searched the word 'face'.
I'm getting lots of repeats on this search - never repeated on the same page, but often on the next page of results. It's not because new images are being added at the start of the list of results. I reset and did the same search, and it was the same images at the beginning.
Has there been a change to the way search results are obtained or presented in 5.3?

I cleared browser cache and it still happens. I cleared cache between changing pages and it still repeated images.
In this example, there are 5 repeats on page 6. I continued and found 6 repeats on page 7. Page 8 was all new.
updated by @lornawebber: 03/12/16 01:42:14PM

This was fixed for us, but is now happening again. We have not applied any updates since the fix was applied by @Brian. I've re-opened the ticket. Sorry.