Hi Nikki!
Sorry to hear you've run into this setback!
It would be helpful to know how your learners were accessing the Storyline course when they ran into the buffering issues. Were they viewing the course through a learning management system? If so, testing the project file with SCORM Cloud can help determine if the issue lies with the .story file, or the LMS itself.
Also, if you're comfortable sharing the .story file, we'd be happy to take a closer look and test the behavior on our end. Feel free to attach a copy here in the discussion or privately through a support case.
Looking forward to hearing from you!