The offset is usually set at 0.0 automatically but for a video I’ve been watching it automatically set itself at +0.3s.
The problem is that it delays the subtitle and the audio happens before that. There’s no option to disable it, so I had to manually reduce the offset to -0.2s by clicking on the -0.5s button.
For personal reasons I won’t be able to share the video or the subtitles (it’s a sensitive documentary).
In addition I’ve noticed that the video player lags a bit whenever I first click on play. This only started happening after the subtitle offset feature was introduced like a month ago.