A safe troubleshooting order
Start from the game's current display settings. Note the current resolution, display mode, frame-rate limit, and VSync state; then change one setting and test the same area again. This makes it possible to identify whether a cap, pacing issue, or tearing changed.
Avoid copying an old fixed setting from a different GPU, display, or game version. Update the game and graphics driver first when a newly introduced issue appears, and include the game version and hardware details in a bug report.
Source and version note
This independent topic appears in the technical coverage on shroomgloom.org. It is kept procedural because no cross-verified universal FPS or VSync value is available.