iPod Restarting Randomly

OK, hopefully this isn't something that is alreada a thread, but I took a quick look and couldn't find any with this situation.

Gat a 4G 20GB iPod for christmas and love it! But the other day something odd happened. I was listening to a song and in the middle of it I heard nothing. When I looked at my iPod it was restarting. The Apple Logo came up and then it booted up and my prefrences were reset. All my music and playlists were still there so I ignored it and went on listening. Two days have passed with no problems but today it did it again right in the middle of a song, and not the same song as last time.

So I'm just wondering if anyone else has had this problem. I'm not too worried about it, I think I'll restore it when I get home tonight but just wanted to see if I'm the only one that has this happen.