[RM2K3] MASSIVE EYESTRAIN WHEN SCREEN SCROLLS?

I'm running RPG Maker 2003's official Kadokawa release, and I've been trying to solve this in every way imaginable with no success.

Whenever I walk around, causing the screen to scroll, the screen "blurs" somewhat, it feels jittery, but strangely without dropping the FPS. It immediately makes my vision blurry.

I tried playing around with the F5 settings to no avail. I think I remember people complaining about something similar in the past, but I can't remember if there was a solution.

Any help, guys? I wish I could use VX Ace instead, but that's ridiculously expensive.

EDIT: Apparently, what happens is that the screen "stops" for a fraction of a second between steps, and that's what leads to eyestrains. No idea how to solve it, though. I try creating a new gamefile, and the same problem arises.

EDIT 2: it happens both in full screen and windowed, and seems to be less strong when I reduce the resolution. Will test it in gf's computer tomorrow.

Unlikely, I have an AMD Radeon R7 260X, which might be old, but come on, it's pixels in 2D at 320x240.