assume_refresh_rate
The option documentation is properly formatted yet
Default: Example: 50 Since: 2.2.2
Use this option to manually specify host refresh ate when refresh rate detection fails. This option in combination with video_sync = auto effectively replaces the old feature where you can use video_sync = full to force full vsync.
Source: https://github.com/FrodeSolheim/fs-uae/blob/master/docs/options/assume_refresh_rate