Is my new Xbox 360 slim faulty?

I bought a new Xbox 360 slim today and well I believe it's faulty, I set it up and within 10 minutes I got the message telling me that there's insufficient ventilation. I set it up in different areas and there wasn't any reason that this message was popping up as I had it in an open area, no ventilation parts were blocked and I had it on it's side on a hard surface nowhere near any heat sources so I don't know why it's doing this, I'm taking it back to the shop tomorrow to get it exchanged but if the replacement does the same thing then I'm gonna be stuck, any suggestions?