ScummVM 1.9.1 Retropie 4.2 controller lag
When running scummVM 1.9.1pre (the current a week ago) on retropie 4.2 with an xbox 360 controller, the mouse cursor, as controlled by the left joystick, lags, like it is being sampled at a low rate. This is present in the gui and in games.
See here or here.
For the first link the work around is to force the mouse to be mapped to the left thumbstick or to use a previous version of scummVM 1.7. The first link believes the SDL1 to SDL2 change made it happen. The second link notices this issue on 1.8.1 of scummVM.