audioOS 9.9.15.4 (build 19L440) is an official Apple over-the-air update for the HomePod mini, released on 2022-03-14T17:12:40Z. The update package is 1.15 GB. This is a delta (partial) update that requires 14.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 457541b8c6129fe67bfa93b4d91f5dedd18a93bd.zip.