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It's currently not possible to prevent notifies from firing by setting their TriggerWeightThreshold. When stepping into the code that fires the notifies I found that the given InstanceWeight was always 1 no matter how much the animation sequence contributes to the final result. It seems like it is being passed the combined weight of all animations rather than individual components.
1. Open the QAGame editor
2. Open the Walk_Loop_Fwd animation sequence and add a Sound Notify to the animation.
3. Give the notify a sound and set its Trigger Weight Threshold to 1
4. Look at the Player_RunBlend Blend Space and notice that the sound plays when the Walk_Loop_Fwd animation is used at any weight, it should only play when it is the sole animation playing.
Head over to the existing Questions & Answers thread and let us know what's up.