DJM-A9 gain indicator lights stopped working

Had A9 since Sept-23. Love it. Been working perfectly. Today started using it and noticed the channel and master gain indicator led's weren't working. Everything else is working fine - audio outputs, channel faders, EQ's, Effects, all fine. Switched it on and off - problem still there.

So.. heres the next twist. I thought updating the firmware might fix it. But when I put the USB into the mixer, nothing happens. I tried two different USB's sticks, formatted to FAT32 before downloading the firmware update. I followed the DJM-A9 Firmware Update Guide to the letter. Its as if the USB wasn't inserted - nothing not a flicker.

I think there maybe a firmware problem and the two issues are connected but I'm out of ideas. Can anyone help please?