iPhone 4s music skipping

I have a new iPhone 4s and I have an intermittent problem with my music pausing itself and then skipping like a sratches cd. What happens is I will pause my music for a little while for some  reason then want to start it again. So I press start on my headphones and I will get one note of the song before it pauses itself again. So I press start again and it pauses again. I press start a third time it will then start playing for a few seconds before skipping like a sratched cd.

I have had two genius appointments and so far I have had new earphones and now a new phone but I haven't had it for one day before it did it again! When we got the new phone we didn't restore from a backup and set it up completely as a new phone, we even synced it for a completely different computer! I can't see any relationship to the songs that it happens on and the songs have always worked on my old IPhone 3G.

It must be something wrong with my software as a new phone didn't  sort it out but me and the geniuses are stumpted!

Thanks

Holly