Sound cue will ignore sound mix settings if settings are called in game instance

When using a Game instance to modify the sound in the editor the sound will ignore settings made by game instance. This issue appears to be occurring only in the editor, as running the game in standalone and packaged does not cause this issue. The user who reported this mentions that the audio device is created after the GameInstance is initialized.

There is a current workaround for the issue, which is to set a delay in the game instance.

Regression:
This issue occurs in the 4.15.3 and 4.16 binary builds of the engine

1. Create a new project (no template or starter content needed)
2. Create a new sound cue > Name it "TestCue" > Open TestCue
3. Add a wave player to the graph and select it
4. The the wave player's details panel set the Sound wave to VR_WorldMoveLoop_02 (You will need to show engine content to select this option)
5. Check the box labeled looping > Save and close the sound cue
6. Create a new Sound mix > Name it "TestMix"
7. In the level blueprint create the setup in Screenshot_01
8. Save and Name the Level "TestLevel"
9. PIE (Expected Result)
10. Exit PIE and Create a new Game instance > Name it "TestInstance" > Open TestInstance
11. In the TestInstantce's event graph create the setup in Screenshot_02
12. In the Level Blueprint disconnect the nodes after Play Sound 2D
13. PIE (Result)

Result: The Sound loops
Expected Result: The sound should fade after 1 second