audioOS 9.9.18.4 (build 22L255) is an official Apple over-the-air update for the HomePod, released on 2025-03-31T17:29:37Z. The update package is 1.19 GB. This is a delta (partial) update that requires 17.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: fc0f7dadea3982a019fd5d7d96a86a5fcc229331.zip.