I looked through quite a number of forums regarding the same problem on ESP8266.
This problem can have 2 causes.
1) Incorrect Firmware. I am sure this is not the case, as all Bolt units have the same firmware uploaded. IF the others work, then this one should be fine.
2) Problems with the power supplies. Now I know that you have tried different power sources for the Bolt unit, but have you tried changing the USB cable that you used?
The problem is definitely in the power supply. So it's either the supply itself, the usb cable or the Voltage regulator on the Board. (The issue at the Voltage regulator seems unlikely as you have tried 3.3v)
Do check with different usb cables, and different power supplies.
If it still does not work, you will definitely be entitled to a replacement.