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I tried to play URU, today, on my Windows 10 machine. In both 3rd person and 1st person, whatever the sensitivity setting, the mouse-look jumps around ridiculously whenever I move the mouse too fast or too suddenly. The result is that I can only turn the player-character with an incredibly slow and tedious click and drag or with the keyboard tank controls.

is this normal?

Is there any way to fix this?

The mouse-look is basically unusable in this way.