Apple released a fourth developer beta firmware for AirPods Pro 2, Pro 3, AirPods 4, and AirPods Max 2 on August 4, 2026, with build number 9A5336b. The update is accessed through the AirPods settings on devices running iOS 26, iPadOS 26, or macOS 26 or later. The firmware adds the new AirPods interface, an Adaptive mode slider, and custom EQ support introduced in iOS 27, iPadOS 27, and macOS Golden Gate, and enables compatibility with the updated Siri AI. Users must connect the AirPods to a powered Apple device to install the firmware, a process that can take several hours because it does not use a standard over‑the‑air update method. The same build (9A5314b) was previously offered to developers and later to public beta testers. Apple is also developing an API that would let third‑party accessories, including Meta’s Ray‑Ban Meta glasses and Quest headsets, pair automatically with Apple devices in response to an EU Digital Markets Act request filed in October 2025. The release follows earlier beta versions and reflects ongoing testing of AirPods software features ahead of the public launch of iOS 27.