Two sounds play for one gift

Symptom

Every time a certain gift arrives you hear two sounds on top of each other.

Cause

Game triggers can carry their own sound, and Gift Sounds can also be set on the same gift. They are separate features, so both fire.

Fix

1. Open Gift Sounds and check whether that gift has a row. Remove it or mute it if the game trigger already plays audio.
2. Or edit the game trigger and remove its sound, keeping the Gift Sounds row.

Related

If sounds overlap for different gifts, that is the queue being per gift by design: each gift has its own channel.