Bose decided to release the firmware downgrade for the QuietComfort 35 and QuietComfort 35 II Bluetooth headsets, even after concluding that the update made available last year did not worsen the noise cancellation of the accessories, as reported by many owners.
According to the company, several tests have been carried out with the QC35 headphones over the past few months, from the moment when complaints flooded the brand’s forums. In addition to laboratory analysis, the company even sent professionals to the homes of some claimants to observe them using the device.
After this thorough investigation, Bose concluded that “firmware 4.5.2 did not affect the noise canceling feature”. In a note released last Thursday (2), the manufacturer revealed that it had even carried out independent tests by a company specialized in the area, which also did not indicate the update as the cause of the problem.
The results showed that, in some cases, the function of isolating external sounds was affected due to the incorrect fit of the headphones – the company said that the lack of one of the 10 guides makes a difference. In others, the failure occurred due to the use of pillows manufactured by third parties, impacting the passive reduction performance. There have also been reports indicating units with mechanical damage, probably due to wear and tear from daily use.
How to downgrade
Although the investigation did not show the update as the cause of the problem, Bose is allowing users to revert to the previous firmware version of the QC 35 headphones.
The firmware downgrade can be done on the Bose website. Version 2.5.5 is for the QC35 phone, while 4.3.6 is for the QC35II model, remembering that the change is optional. If your accessory is functioning normally, it is recommended to leave the latest firmware.
The American company also released the video below with guidelines for solving noise cancellation problems.