Project locks up when returning to menu slide

Help! I am relatively new to Storyline, and I cannot figure this out.

I have a new project with 6 scenes: 4 content sections, an intro, and a menu. Only sometimes, when returning to the menu, the project locks up and shows a spinning wheel. This seems to happen most often the 3rd time the user tries to visit the menu (intro, menu, section 1, menu, section 2, *locks up when trying to return to the menu*). 

Through my troubleshooting, I have found that the issue is more  likely to occur if the user navigates through the content via the buttons on the slides rather than with the player. I have also found that if the sections are performed in the wrong order, it still seems to be the third time the menu is visited that it locks up (i.e. intro, menu, section 2, menu, section 1, *locks up when trying to return to menu). This led me to believe the issue was with the menu scene. However, when I isolated the menu scene by copying it into a new project with blank content sections that just contained one slide with a button to return the user to the menu, I was not able to get the project to lock up again. 

This problem happens 75-ish% of the time. It happens in Storyline preview, as well as when published on review 360 and in our LMS.

It is really frustrating because this project needs to be pushed out, and I have no idea what else to try. I really do not want to start over. What am I missing?

Any help is greatly appreciated - Thank you so much in advance.