Place it just before the message or parcel is revealed, then follow it with a bell ding to mark the inbox update and a door knocking cue for the delivery, keeping the mail moment first and the reactions after it.
關於此聲音
This five-second clip is a short spoken announcement that mail has arrived, kept simple so the message itself stays the focus. It feels light, cheerful and a little playful, turning an ordinary inbox update into a small moment worth noticing. The plain delivery makes it easy to recognise and fun to drop when a new message appears.