audioOS 9.9.12.4 (build 16G78) is an official Apple over-the-air update for the HomePod, released on 2019-07-22T17:29:21Z. The update package is 2.54 GB. This is a delta (partial) update that requires 11.2.5 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f981892b7fdbd0f46c7316127808e72e8ac0a41c.zip.