I have a nano 6th generation iPod. It was working fine till the day it started malfunctioning. It stops playing music as soon as it goes to the sleep mode then every time you have to unlock it by pressing the power button and again click on the play and it starts playing then.
iPod nano, iOS 7.1
If you have not already, do a Reset (restart) of the iPod
Learn how to reset your iPod - Apple Support
If that does not help, you should try doing a Restore on the iPod using iTunes. This erases the iPod, reinstalls its software, and sets it to default settings. The Restore button is on the iPod's Summary settings screen in iTunes.
Get a flashlight and inspect the headphone jack of your Nano. Use a toothpick and clean out any lint/dirt/debris/mouse droppings/etc. that you find. It may be stopping your headphones from being plugged all the way in (their should be no gap between the plastic on the headset jack and the body of the Nano).
nano 8GB (6th generation)
