70ms 60 FPS, rubberband soon as I enter combat (SHADER bar spiking)

This has been an issue for several leagues now and I'm not sure what's causing it. I've tried everything and nothing seems to work. Have reinstalled the game and everything in between. E-mailed GGG support but I guess they no longer do that either.

So... I'm turning to the forums to see if anyone managed to fix this same issue, although I imagine many people are experiencing it and few - if any - will have fixed it. If they did fix it, they're probably not even on these forums anymore, but I don't know where else to go so here I am. (GGG please help)

Running windowed fullscreen 1920x1080 on Predictive Mode (Lockstep just causes stutter lag when I enter combat instead); have turned pretty much every option on and off... RTX3060, i11700, 16GB, Win11.