Strange behavior using OnFocusLost in Training Simulation

Hi all. I am building a training simulation using Captivate 2017.

I am using the OnFocusLost to trigger an action to move to the next slide. The user types a term into a click box. The user is instructed to click outside the box to continue. It seems to work OK and moves to the next slide.

But once it moves to the next slide, everything on that next slide pauses immediately. Audio won't play and the failure caption from a click box on the new (second) slide comes up immediately.

I can click into the box on the second slide, which successfully triggers an action to move to a third slide. (I tried moving the click box on the second slide back a few seconds to see if that would ease the problem. But then the second slide freezes completely and I can't even activate the click box).

Interestingly, this happens on every slide where I use OnFocusLost to trigger the action to move to the next side. The following slide freezes immediately. And it doesn't happen when I use the Enter key to trigger the same action. But my customer doesn't want the Enter key, which is why I tried OnFocusLost.

Anyone have any ideas?

Thanks in advance.

Scott