Auto-selecting Closed Captions?

Hello. I'd like to help, but I'm not sure I understand the exact problem. Before I suggest something that won't do you any good...😀
If you want to trigger the appearance of closed captions made in Storyline just for this video just for the slide where your video is playing, without clicking on the CC button in the Player, and they're no longer automatically on the next slide, that's super easy. But is that really your question? 

Yes, I guess you mean what I was trying to say. 😅

As the audio for just this video will be in a different language to the rest of the course, I want the subtitles to appear when the video starts, without having to manually select them from the CC menu of the video player.

OK, this is mostly due to my difficulty in understanding English sometimes...😁
In this case, it's super easy.
In Storyline, the appearance of subtitles depends on a built-in true/false variable: Player.DisplayCaptions. Have a look at the table of “built-in” variables. True: you have close captions. False (default): you don't. So, all you have to do is create a trigger: // Set the “Player.DisplayCaptions” variable to the value “True” WHEN the chronology of this slide BEGINS // (of course, you've already created your Storyline subtitles on this video) So it's as if you clicked the CC button as soon as the slide starts.   Create a second trigger: // Set the “Player.DisplayCaptions” variable to “FALSE” WHEN the timeline of this slide ENDS // In this way, the next slide will not be automatically subtitled. That's all there is to it. Am I clear enough? Does this help?    You can check by “displaying” the variable on screen that “Player.DisplayCaptions” changes from TRUE to FALSE and vice versa every time you click the CC button.

Thanks, ThierryEMMANUEL. Yet it means that I can't do that in RISE, I have to do it in Storyline and import the video from there into RISE, correct? 

(So far I've only worked in RISE. Finally gotta dig into Storyline, I guess. 😅)

Hey ThierryEMMANUEL. Sorry for answering so late. I was busy with other projects. 

I've finally come around to testing Storyline, but so far it's hard to get started. For me at least, it's not very intuitive to use, I'd probably need a proper tutorial or workshop to get a grip of Storyline. But I've found a workaround, using a video editing program (DaVinci Resolve in my case) to burn the subtitles into the video. 

Thanks for your help! I really appreciate it. 🙂

Hello managerSeminare . Thanks for letting me know. The most important thing is that you've solved your problem, however you can.I am happy for you.