ipod nano 7th gen won't turn off

I recently bought the 7th generation iPod nano (the version is 1.0.4 Mac) off of Apple's site. It works completely fine, but the screen will continually light up every couple of minutes or so even if it's flat on my desk and I haven't touched it at all. It also does this if I put it in the "deeper sleep" setting by holding down the button in the upper right hand corner. This completely drains the battery within a couple of hours, which is highly inconvenient and very unexpected for a portable music playing device. I have tried restoring the iPod, turning on and off the bluetooth, and changing the brightness of the screen. Is there any way to fix this problem?