In July, Apple began providing developers with access to a beta version of the AirPods Pro firmware to test new features ahead of their release. Last Friday, Apple released a second version of the AirPods Pro firmware (4A362b), but it went under the radar until today when it was shared on Reddit.
According to Apple’s developer website, the second AirPods Pro firmware update adds support for Conversation Boost, a feature that was missing from the first beta.
Conversation Boost is an iOS 15 feature that uses the beamforming microphones in the AirPods Pro to boost the volume level of conversations, which is great for those with mild to moderate hearing challenges.
The initial AirPods Pro firmware beta added support for FaceTime Spatial Audio and Ambient Noise Reduction, two other AirPods Pro features that are coming in the iOS 15 update.
Only registered developers are able to install the AirPods Pro firmware, and the installation process is rather complicated and requires Xcode. Therefore, the test version firmware of the headset cannot be tried like a mobile phone. It is recommended that general users wait for the official version.
Carol Yu 
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