audioOS 9.9.15.4 (build 19L440) is an official Apple over-the-air update for the HomePod mini, released on 2022-03-14T17:12:41Z. The update package is 478.83 MB. This is a delta (partial) update that requires 15.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 203e713f02d96ff931117dfd77cd201d5207b3cc.zip.