USB-BT4Le not recognized

I have a problem with my usb adapter. When I insert the the adapter on my computer ( ubuntu 12.10 kernel 3.7.0-7-generic , 64 bits), I have no blue led, and no information on lsusb or dmesg.
The first time when I plug it, I hadn’t problem (adapter appear on lsusb and blue led light) but since it’s doesn’t run. I have try on Windows and it’s the same problem (no blue led and no display on usb device).
What can I do ?

Thank you for your help

Hello Helene,

Thank you for contacting Plugable Support! This issue sounds hardware related, and we would like to get a replacement unit shipped out to you as soon as possible. Could you please email us at support@plugable.com with the following information:

Your Amazon Order ID (found in your order confirmation email)
The Serial Number of the unit (found on the back of the packaging, if you still have it)
The best address to ship a replacement to

As soon as we get that information, we will get a pre-tested unit shipped to your door!

Thank you!