Hi I am from India I have bought the Bose QC 35 ii in DEC 2019 it came with firmware 3.1.8 , its ANC quality was really nice until its firmware automatically updated with Bose connect app. I have seen significant noticeable difference In ANC after firmware updated to 4.5.2 . I couldn't see much difference in ANC low and high mode . after researching this issue on Bose community forum I have seen lot of people having same issues regarding firmware update . so I decided to replace the device.
well after I received my new device and I have seen its already came with firmware 4.3.6 , my previews experience with firmware I didn't update to latest firmware 4.5.2 . but I feel its still not the good as the device I have bought with built in firmware 3.1.8 .
Is there anyway to rollback the firmware to 3.1.8 ?