iPod iPod music skips Like a CD

I'm not sure what's going on with my Ipod shuffle, but I have been using it for a while and up until now it hasn't given me any problems. but just last week I noticed that some of the songs started to skip... like a cd skips when it's hit. it has gotten progressively worse. Since these songs were downloaded some time ago and have not given me any problems until now, I don't understand why this has started to happen. The music is even skipping when I play it from the music library on itunes in my computer.
DOES ANYONE KNOW WHY THIS IS HAPPENING???

nope

they were ripped fine.... they were playing fine both on the ipod and on the computer for 6 months. and then last week some of the songs just started skipping, both on the computer and on the itunes...