Created attachment 185346 [details]
PDF file that shows the issue

SUMMARY
A PDF file with a video included (set to autostart) plays well in the normal view. In presentation view however, the normal view remains open in the background. Videos play in both views _almost_ simultaneously, causing an unpleasant echo. (For context, I am typically playing music videos like this). 

STEPS TO REPRODUCE
1. Open a PDF file with embedded videos set to autostart
2. Start presentation mode
3. Click through to the slide with the video

OBSERVED RESULT
Video with sound is played twice with a slight delay, which sounds unpleasant in many scenarios.

EXPECTED RESULT
Sound is played once only

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.18.0
Qt Version: 6.9.2
Kernel Version: 6.16.8-arch3-1 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 7840HS w/ Radeon 780M Graphics
Memory: 32 GiB of RAM (30.7 GiB usable)
Graphics Processor: AMD Radeon 780M Graphics

ADDITIONAL INFORMATION
I have attached a PDF that can replicate the issue with a small video (needs to be in the same directory as the PDF). The click should just be a single click, but in presentation mode it sounds like a double click. I've also attached the tex file used to create the PDF.

If someone points me to roughly the right area of the code base I'd be happy to have a go at investigating/fixing it, although my C++ isn't great.