That racket is what neighbors in SoMa tell us they've been hearing for weeks.
After our report Monday night, Waymo got back to us with new information.
RELATED: Waymo cars honk at each other throughout the night, disturbing SF neighbors
The company says the honking is happening because of software meant to prevent slow-moving crashes.
For example, if someone is slowly backing out of a parking spot and doesn't see you, you'd honk if they got too close.
Put a handful of Waymos in a parking lot and that's what you get.
The company says it's adjusting the software.