Edit: related to this issue?

I am finding that when I preload a scene that contains a Movie Player actor, the movie file immediately begins to play but with the video hidden (e.g. I can hear the audio begin playing, but nothing is sent to the projector), even though the scene has not yet been activated. When I subsequently activate the preloaded scene: (1) the video becomes visible on the stage, and the audio continues in sync with the video; and (2) I can see that the position output parameter of the Movie Player is not zero (e.g. it began playing when I preloaded the scene earlier, not when I just activated the scene).

This is happening only on my Windows laptop. It works as it should on my old Mac laptop (quite old version of Isadora). I don't remember this happening before I just updated to Isadora 4.5.1.

This happens on my Windows laptop even when I create a new, blank Isadora document and add the following three actors:

Scene 1:
[Preload Scene] actor 

Scene 2:
[Movie Player] -> [Projector]

The only workaround I can find is to not preload scenes, but this is a problem for my application which requires intricate cueing.

Isadora 4.5.1, Windows 11, Intel i7-13700H. H264 file with stereo audio track.

Many thanks in advance for any advice.

Jonathan.