My brand new iPad air has been completely unresponsive and needed to be "hard restarted" twice. What's up with that?

3 days ago, I purchased a new iPad air. I've installed a few apps on it and have generally just been playing with it and figuring out the OS. Yesterday, while trying to wake it up, I noticed the device was completely unresponsive, the screen would not even turn on. I executed a hard restart (held down home and power for 10 sec). That seemed to remedy it for the time being but it just happened again. I'm concerned that this will be a recurring issue and will possibly degenerate into a bigger problem for my new iPad. Is this a known issue? If so is it a hardware or software related problem. Any help would be greatly appreciated. Thanks.