Erratic mouse movement in Nosferatu: The Wrath of Malachi

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So most times the mouse movement is very erratic and not smooth, there are no in-game or ini/registry options for mouse sensitivity, acceleration, smoothing or anything like that. I tried several polling rates (125, 250, 500 and 1000 Hz), because some old engines have issues with higher polling rates, but nothing helped in this case. Can someone figure out the problem of the mouse input being so erratic?

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Update: I managed to fix this problem completely by using a program called RInput, it injects a DLL containing raw input code which bypasses the ingame's input code.