Firmware update

Every time I try to update our brain, I get the message that there is a USB connection failure. I am using the Mac version on a MacBook Pro. What yould be wrong?


We will need to isolate the problem a little bit more, so can you please try another brain on the same computer?
If you do not have a spare brain, then can we try another computer?

Also this problem sometimes is caused by a bad cable, so if you could please try another cable.
Its a regular Android phone charger cable.