audioOS 9.9.18.1 (build 22J580) is an official Apple over-the-air update for the HomePod (2nd generation), released on 2024-10-28T15:30:08Z. The update package is 1.41 GB. This is a delta (partial) update that requires 16.0 already installed. This update is currently signed by Apple, so it can be applied from Settings › General › Software Update.

Payload file: 3b6ab9b44f3ebbcebe5da278f2bbd136a6c6c9f74d3c9b84b87e44599f275eb0.aea.