Apple has been unusually frequent with its firmware updates for its AirPods product lines. The relatively high pace of updates continued with another AirPods firmware update.

Deployed on Monday, the latest firmware updates are intended for AirPods Pro 2 with Lightning and USB-C charging cases, as well as both AirPods 4 models.

It is unclear what has changed in the firmware, build 7B20 for AirPods 4 and 7B21 for AirPods Pro 2. It is likely that the updates will bring bug fixes and performance improvements to audio equipment, with all details known if Apple releases a release note.

Apple’s last firmware update was for the AirPods 4, which arrived on October 29. This was an update to version 7B19, the same version given to the AirPods Pro 2 in an update the previous week, but without the Hearing health features.

Users can’t force AirPods to update, but they will update automatically when paired with a iOS device and placed in its charging case.