Have a 7th gen ipod and it constantly skips

We just bought a 7th gen iPod nano and when I try to play music that's been downloaded onto it, it skips. Either further into the same song or to an entirely different song all together.

I've restored the factory settings on the device but the problem returns immediately. I've seen other threads about it skipping songs but none seem to have the same problem. I happens regardless of whether I'm holding the device or laying it on a steady surface. The windows defrag option doesn't apply since we've only got OS X systems.

Are there any other solutions I can try?