ios 7.1 update - battery

I'm pretty sure it's ios 7.1 (came out a few days ago) but my 5g ipod isn't charging. It shut down on low battery and when I put it into charge it's just showing a 'battery picture' just loading a red 20% of battery on and off. It doesn't actually turn on though I know it's been charging long enough.

Is this with the supplied charger?

If you're using a working Apple charger or have it plugged into one of your USB ports (not a hub or keyboard) and it's still not charging, it might mean you need a new battery.

Could it be a bad cable?