Sound mixers do not properly override variables within a sound class. This prevents users from being able to modify variables such as volume or pitch quickly and efficiently by using the push/pop state features for mixes.
Note: Though image only shows push sound mixer nodes, this was tested with push/pop mixer nodes as well as clear modifiers + push modifier node combinations. In no situation did the mixers apply any effects.
1. Open Editor (any project).
2. Create new sound class.
3. Create new sound cue.
4. In sound cue, create a wave player (any sound) set to looping.
5. Create a soundclass node of type new sound class and plug this between the wave player and the output.
6. Create two sound mixes, one that increases volume to 10.0 and one that lowers volume to 0.0.
7. Set sound class to have one of each mix modifier by presing "Adds Element" pin next to Passive Sound Mix Modifiers.
8. Save all sound mixes, classes, and cues created.
9. Create new blueprint according to attached screenshot.
10. Place a copy of blueprint into level.
11. Press PIE.
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