My new WDTV Live turns off after some seconds

Hi, yesterday I got my new WDTV Live, after reading the very short start guide I proceed to connect the unit to the tv, to the power, etc, and it turned on, I tried the HDMI first and when I saw the TV  screen it was black, so I changed the cables and tried the composite, same result, then I noticed the unit was off… tried to turn it on and the power light went on for 2 seconds and then off again… I disconnected the unit, read the manual in order to know if I should do something different, nothing… I connected again the unit, this time I saw the splash screen (I was very happy), then the menu and puff “no signal” and 2 or 3 seconds later the unit went off again… again to the forums, pressed the reset button, connect again… 2 or 3 seconds of the splash screen and turned off again… I disconnected the unit for 30 minutes, and connected again (no usb drives, only the HDMI cable) this time the menu screen worked for 2 minutes and then off again… I repeated the process several times (disconnect, wait 10 minutes, connect, and try), this time I disconnected everything, leave the unit disconnected for 10 minutes, connect to the wall (only, no TV, no usb flash, no disc, nothing just power cord), and check… after 2 minutes the unit went off again.

I touched the unit and it’s very cold, so I dont think is a problem with heat or something like that, I live outside of US so get a refund or return it’s not really an option (I asked to my box service and I’d to pay for the submision and the tax again… that will cost me around the same value of the new unit). I chose WDTV over asus because I read they’d very good customer support and the units are flawless,

PLEASE HELP ME!!!

Im seeing in other post that the problem with turning on relied on the AC adapter, I will try a new adapter tonight… I really hope this solve the problem, it will be very annoying to throw a unit 1 day old to the garbage.