Apple recently updated the firmware of AirPods to version 3.5.1 from 3.3.1 without any prior notice. It is not known as to what exactly is included in the latest update.
It can be assumed that the updates were released to fix some of the problems reported by several users mainly issues with Bluetooth connection. Another problem is the quick discharge of battery when AirPods are in charging case.
The updates are installed automatically when the AirPods are in their charger case and connected to an iOS device. This might be the reason why many users probably wouldn’t have noticed any change.
If you want to check the version of latest Firmware for AirPods, go to Settings > General > Information > AirPods.
Despite the criticism and problems, AirPods are still well received by even its critics. The AirPod is known for its sound quality. The new W1 chip sits inside the new AirPod headphones. It helped Apple to fix a lot of challenges regarding wireless audio. The chip uses Bluetooth for connectivity and seamlessly connect to other iCloud connected devices such as iPhone, iPad or any Mac devices. The W1 chip is also effective in keeping power drain to the minimum.