On December 16, Apple released 2C54 firmware for AirPods Pro, which improved sound quality. However, after a few days, it stopped releasing the update, as users began to complain about the deterioration of noise reduction.
The same confirmed RTINGS resource :
After upgrading to firmware 2C54, we re-tested the headphones, and our results showed a fairly significant decrease in noise reduction. This means that with the noise canceled on, these headphones will not cope with the suppression of third-party noise, as it was before.
In the same note, reporters noted that Apple did a good job on low frequencies and improved the sound of the “airpods”.
Now it remains only to wait for the company to release a corrected update. [ MacRumors ]