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 1.26 GB. This is a delta (partial) update that requires 17.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 655e66234d5cc8c67c0a03f8a15f3ed12471ef43.zip.