I use the speech function in notebooks to review collected excerpts. Once activated, it reads aloud all excerpts in the order of the map.
A special case of excerpts are audio / video excerpts. If View > Documents in Mindmap Notebook is disabled, the excerpt’s title and comment is read aloud and then afterwards the audio/video is played. That’s perfect!
However, if View > Documents in Mindmap Notebook is enabled, then while the text is read out loud the audio or video starts playing at the same time - in parallel. So text-to-speech is not really usable in this scenario.
I believe it would add value, especially for reviewing video excerpts, if it was possible to do the review while viewing the larger video. The behavior should be the same regardless of which setting is used for View > Documents in Mindmap Notebook.