On 9/14/2016 I sent email to exchanges@hak5.org, with problem description and copy of receipt/packing slip. I'm not sure what is the proper current procedure for returning defective unit, so I am also notifying you directly. I think this is a very innovative product with the potential for a lot of uses, but I cannot use the current unit due to being unable to put it into DFU mode. As I stated in my email, I am well aware of the correct method of putting this unit into DFU mode and have tried all practical methods and suggestions listed on this forum site, none of them are useful if I cannot first put unit into DFU mode. I am requesting a replacement usb rubber ducky.