UE4 package crash: "Could not find SuperStruct AkAmbientSound"

Question

Hi all,

I attempted to create a package for my UE4 project for the first time, and the package crashes at startup with the following message:

I'm using a blueprint actor that extends AkAmbientSound, do I have to do anything more during the packaging process in order for that to work as intended? The game is running fine in PIE.
This is a blueprint only project, no C++.

Thanks !