AIRPODS MAX FIRMWARE WON'T UPDATE

[Robertbates009]

Hello, please how can I get my APM to update? Tried everything i could find online. Mine is still stuck in version #4E71 of last year may. Sound is crappy af, Bass, spatial audio and ANC almost non-existent, irregular battery %. Please help. I lost my APM case for a while and thought that could be the reason why it's unable to update the firmware. I borrowed a friend's and still it is yet to update. Please help

 

[Shanghaichica]

Where did you purchase them from?