audioOS 9.9.17.3 (build 21K646) is an official Apple over-the-air update for the HomePod (2nd generation), released on 2024-01-22T18:29:36Z. The update package is 1.18 GB. This is a delta (partial) update that requires 16.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 11ec0fcba0df02d210780416c944e26e7664f9a1.zip.