audioOS 9.9.15.4.1 (build 19L452) is an official Apple over-the-air update for the HomePod, released on 2022-03-31T17:15:57Z. The update package is 1.17 GB. This is a delta (partial) update that requires 14.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 8afe7cb71d50aba9f78f40221e3eceb3ec966331.zip.