N300 Wifi Extender wont power on

So today I bought an N300 wifi extender, as at my current house I live in the basement and get poor signal. I got the thing home, plugged it in and the lights flashed on for a milisecond, then died.
No worries I thought, as the manual says give it a minute to power on. So I waited. And waited. And waited. 
An hour later and still no luck.

So, is there anything I can do, or should I just head back to the shop (tomorrow) and swap it for a new one?

Also, I've not read much into the N300, have there ever been any problems with the Virgin Media superhub? 

Thanks in advance.