audioOS 9.9.18.4.1 (build 22L261) is an official Apple over-the-air update for the HomePod (2nd generation), released on 2025-04-16T17:28:46Z. The update package is 1.44 GB. This is a delta (partial) update that requires 16.6 already installed. This update is currently signed by Apple, so it can be applied from Settings › General › Software Update.

Payload file: 125c7d007d9fe3df8d4a69ad66d81fd861ab4c816c3d3470b795fc9bc53892ad.aea.