[Gameplay] Images Flashing on Screen During Gameplay

For the last patch or two, I've had images that randomly pop up on my screen while in-game. They're images from the game files, so it's not like it's some weird browser virus or anything ;)

This happens randomly, sometimes only once, sometimes multiple times within the game. I'd screenshot it, but I have no way of predicting when, where, or what image it will flash on my screen. It can be any image, but I've noticed that when Warwick is in the game, it tends to be his portrait (spooooooky scaaaary). But not always.

I've tried repairing my client, fresh installing, my graphics drivers are up to date, etc. I know I have friends who have also been seeing this, and I do see it from time to time on pro streams. I'm not sure whether it flashes too fast for most people to notice, as a lot of people just ignore it. It's getting annoying, and it can be a little disorienting at times too.

For the hell of it, here's my system specs: Win7 Core2Quad @3.5GHz ATI Radeon R9 8GB RAM

Separate from this issue, any chance of changing the health bars back so they don't JUMP to the current life when you move your camera over the person? It always scares me when I look mid and see the midlaner lose 1/2 their life out of nowhere.