"Meet Reality Composer Pro" - Spatial Audio Problem

I'm following the Meet Reality Composer Pro walkthrough and ran into something that didn't function as expected.

When I got to the step where I add five "Bird_With_Audio.usda" references to the scene, I found they did not play audio. After some trial and error, I found that Preview > Resource in each of their Spatial Audio items was set to "None." If I click the dropdown menu, I see several "Bird_Calls" groups to pick from.

I checked the original Bird_With_Audio.usda that I had created, and the "Bird_Calls" audio group was correctly assigned and worked. I tried dragging a sixth Bird_With_Audio into the scene and confirmed that the Spatial Audio item suddenly empties, rendering the bird silent.

I was able to go through each of the five birds and set their Spatial Audio Resource to Bird_Calls, and the group worked like the video demonstrates.

While this fixed the issue, as a beginner I'd like to know why this happened. It doesn't seem right that I would build and item and then have to re-attach any sounds to it when I place it in the main scene. So…where did I mess up?

"Meet Reality Composer Pro" - Spatial Audio Problem
 
 
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