audioOS 9.9.15.5.1 (build 19L580) is an official Apple over-the-air update for the HomePod, released on 2022-05-25T17:16:52Z. The update package is 1.25 GB. This is a delta (partial) update that requires 13.4.8 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 62fa9cbf4ae64dc98b8623091241818c2ed91e64.zip.