audioOS 9.9.17.4 (build 21L227) is an official Apple over-the-air update for the HomePod (2nd generation), released on 2024-03-07T18:16:33Z. The update package is 716.47 MB. This is a delta (partial) update that requires 17.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 7a2836bf0b5ae2fc33ef5c400a2dc71fbcbec4b1.zip.