Audio not starting on individual slides

Problem: When I test, sometimes audio doesn’t start on a specific slide. (I have a button to click at the beginning of the elearning module, so the audio IS working overall.)

Sometimes, I can correct it by pressing pause and then replay in the toolbar, or by going back to the previous slide and then entering the current slide again.

I’m trying to troubleshoot, and wondered whether this red line in the timeline has something to do with it? If not, other ideas?

edited to add detail

Hi @Chante,

Could you please share us the project and its external data folder named in the PROJECT_FILE_files (if any) to support@atomisystems.com so that we can better investigate?
If these files are large, you can upload them to a cloud storage site like Google Drive then send the download link to us. Make sure that you have given us the right to access the folder/ link.

Thank you for your cooperation.

BR,
Quynh Anh