Ok i'm back.
I was messing around with my laptop troubleshooting this problem and I found out that I get the same issue!
What I did to fix it is, sticking the flash drive into another usb port. For some reason some mac computers get messed up with the power flow to the usb port. This problem that you are having is highly probable that your computer is not giving the desired amount of power to the port.
To sum things up, if you are using a laptop, plug in the charger. And change the usb port that you are using.
Now if the solutions that I provided above still do not work try this.
Go into disk utility and change the name of the flash drive, now hit erase.
Get back to us and tell us how its going!
-Patrick