Audio Glitch in LMS

Hello!

We've recently uploaded a storyline SCORM 1.2 file to our LMS (SuccessFactors). During our quality review checks, we noticed the following situation. When a learner exits the course before finishing it and then opens the course later to complete, whichever slide the learner left off on - the audio is not audible unless the learner clicks the replay button or selects the previous slide. The audio performs as expected if the learner works through the course without exiting though. 

We did some general troubleshooting and created three new SCORM files to test but experience the same thing each time. This is a new glitch for us. Has anyone encountered this before? Any ideas on what may be causing this?

Note: The audio files were created using Natural Reader.