Windows 8.1 Wallpaper Flicker After Transition

I have had a stable installation of Windows 8.1 Pro for several years now. I have a folder with about 3000 images that are shuffled through using the default Windows 8.1 Personalize options, desktop background slideshow. No third party software is used for this.

I have a dual monitor setup. Extended displays.

The problem I am suddenly having is that when a wallpaper fade-transitions from the current image to the next, once the fade animation has completed, a small area/portion of the previous image will flicker onto the screen for a split second, usually near the bottom. It does not happen every time (1 out of 10 or more), and I can not cause it to happen on purpose, even though it will happen when transitioning automatically, or through the right click, Next Desktop Background option.

There have been some changes to my system, but they did not cause any immediate issues.

• About three weeks ago, I upgraded to a Geforce GTX 1070.
• About 2 weeks ago, my employer updated their VPN client. The client is not loaded at startup or as a service. My computer boots pretty clean with only GUpdate running at start for Chrome.
• About 2 weeks ago I accidentally deleted my picture library folders, and had to create new ones because Windows would not recognize a new folder structure under the old library name. (As if it was only reading old structure from cache) As a result, the 3000 images are all in one folder now, as opposed to being separated into folders by category.
• About 1 week ago I added 8gb of RAM identical to what I currently had installed for a total of 16gb (4x4 of identical sticks)

The issue did not immediately follow any of these changes. It just started 2 or 3 days ago and its driving me a little bonkers.

I have updated to the newest Nvidia drivers, and reviewed all settings for errors, disabling things such as desktop scaling (even though it wasn't in use)

It also does not seem to be tied to any individual program running, because the flickering can still occur while no programs are open, immediately following a cold boot.

Any help would be appreciated. I did google search but the results mostly pertained to full display flickering. Not just wallpaper image related problems. I did see one person with the exact same problem description as mine, but it pertained to Windows 10, and was not given a reply to try for myself.

Thanks.