audioOS 9.9.17.0 (build 21J354) is an official Apple over-the-air update for the HomePod, released on 2023-09-18T17:26:30Z. The update package is 1.05 GB. This is a delta (partial) update that requires 16.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 313e8bdcf714b32f8eedf64435788a95bc6867a3.zip.