Get the app
Sounds made and shared by TesCam Studio drivers. Tap play to hear one, download it, and your Tesla plays it when Actually Smart Summon reaches you.
Every sound saves as ASSChime.wav, the exact name your car looks for.
Put it at the top level of the drive, next to any lock sound and not inside the TeslaCam folder, and plug it into the car.
Controls, then Autopilot, then Customize Summon, then Completion Sound, then USB. Summon the car to hear it.