I've been having this issue. It doesn't happen immediately. It starts to resemble a slideshow after 10-30 minutes of gameplay. From my observation, it's only other player models that are affected. Map animations (like water) are normal. My own animations are normal. Everyone else seems to skip around. It happens in the middle of strategus battles too, so I can't blame it on map changes. I did notice my FPS (max 120) would drop significantly when it started happening.
I tried lowering or turning off a bunch of performance settings that were suggested in this and other threads.
Textures on Demand off
Auto-Exposure off
Depth Effects off
Instancing off
Max frames set to 59
With those adjustments, I found myself warping around. When I asked on teamspeak, I was told I seemed to be playing normally. My ping was fine. My FPS was fine. I was just warping around on my end for some reason.