audioOS 9.9.15.1.1 (build 19J582) is an official Apple over-the-air update for the HomePod, released on 2021-11-03T17:10:18Z. The update package is 1.22 GB. This is a delta (partial) update that requires 13.4.6 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 99c19f4f3b9ed0e8ae311ab8a4a87d9d9cab2dec.zip.