Problems with headphones after firmware update

[CeeCee]

I have a pair of WF-1000XM4 earbuds. They are little over a year old.

Lately, since the last update to firmware 2.0.1 the left earbud has an extremely low volume. I've tried several different devices. I've tried everything I can think of.

Is there any way to back up to a previous version of firmware? Or if anyone has a sure way to fix this? Please, I've been so happy with these earbuds and I am very disappointed that they would only work properly for 16 months...

[TheMaze]

Hi

Did you check if the actual earbud is clean or that no ear wax residue in the eartips?

You can also try to reset the headset: https://helpguide.sony.net/mdr/wf1000xm4/v1/en/contents/TP1000428696.html

Or initialize the headset to its factory defaults: https://helpguide.sony.net/mdr/wf1000xm4/v1/en/contents/TP1000428697.html