The reason the the sound isn't playing is there is no XAudio2 instance on "Layout 3", even though the XAudio2 object is on "Layout 1" and has global enabled. Global doesn't mean it will exist on all layouts, it means that after an instance is created it will still exist when layouts are changed at runtime.
A simple fix would be to create an XAudio2 object at the start of "Layout 3". It is also a good idea to check if there are any XAudio2 instances before you create another to prevent distortion caused by multiple instances.
+ System: Start of layout
+ System: CountMatching("XAudio2") Equal to 0
-> System: Create object XAudio2 on layer 1 at (0, 0)
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