Right side of the earphones won't play music.

I was listening to music and the iPod Classic was working fine, and then it suddenly stopped playing through the right side of the earphones. I thought the problem as from the earphones, but they worked just fine on other devices, and any earphones or headphones I tried for the iPod it was the same problem. But when I press down on any side of the iPod, or when I push the pore of the earphones sideways they work fine, until I release the pressure and then the right side stops working again. What can be the cause of the problem? I am currently out of the States, and don't fully trust the shops where I am now.