Hi, I had this issue ...
I then tried to start the eDRUMin software as admin and it runs through the update...
You said, that isn't necessary ... but ... he should try it.
Trouble Updating Firmware
Re: Trouble Updating Firmware
I have no clue why but nothing worked to update the firmware until I tried while connected using my powered usb HUB. Then BAM...updated in the blink of an eye. Case closed for me I guess but I still don’t know why I couldn’t update when connected directly to the pc.