audioOS 9.9.18.0 (build 22J357) is an official Apple over-the-air update for the HomePod (2nd generation), released on 2024-09-16T17:25:24Z. The update package is 1.38 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: c3b399d213788097c350352a8824e36244786be9e5c19e7291f54653b44493b8.aea.