iPod 120gb ipod classic continuously changing songs

I ordered a brand new 120gb classic from apple's site a few weeks before christmas and got it as a gift from my parents. It worked just fine the first two weeks or so, with only a few minor issues. Everything was a bit laggy, but overall it worked nicely. Now, as the title hints at... I'll start playing a list of any size, and after 1 or 2 songs, it will cease to play, and instead change songs over...and over...and over again in 4-5 second intervals. Anyone else have this problem? Or any solutions? I'm quite disappointed, apple generally has a pretty good rep with these things. Right now, it's making it impossible for me to listen to music, without going through my list and picking one song at a time. Any help is more than welcome, thanks for your time.