Bethesda released a new Deathloop patch today that it says will partially fix for the game's occasional stuttering issue. Version 1.708.4.0 is available now on both the Steam and Bethesda launcher versions of the game.
Bethesda says the patch "addresses an issue experienced by some players on PC whereby mouse-based camera movement could result in the appearance of 'stutter.'". Bethesda added that a separate stuttering issue seemingly caused by high framerates on PC will be addressed in the future once they have more information.
Despite positive reception overall, many of the game's negative reviews on Steam included comments about stuttering during gameplay. While theories about what caused the stuttering ranged from everything including Denuvo DRM to memory write access errors, Digital Foundry's latest video on the subject first indicated that the problem lied with mouse-based movement.
As Digital Foundry tells it, the stuttering was simply a result of the camera movement stopping every 14 frames if playing with a mouse on 120 fps. They say it's not really your GPU or CPU struggling to produce a high framerate, it's the camera animation. If you change your framerate to something like 100 fps, the camera actually increases its speed for one frame, adding an unintended (if slight) extra bit of distance to your mouse movement. Variable refresh rate monitors with G-Sync or FreeSync at unlocked framerates would also appear to stutter.
A less frequent issue Digital Foundry discovered is that when you load up a new map, every 600 frames may be a redundant frame, causing an actual stutter. It appears that a simple reboot of the game or loading a new map may fix the issue. We haven't had too much trouble with stuttering issues in Deathloop up until now, and after a brief test in the new patch, the game seems to be running as well as it was before.