problems with headphone jack on ipod touch

[tigergrad28]

i bought an ipod touch from a guy the other day and when i got it home and tried to test it out, I can barely hear the music through the headphones. It sounds as if the headphones are not all the way pushed into the jack, but they are. I can put it on my iHome(or whatever it is) and it plays fine but i can hardly hear when i connect the headphones. Also, I bought a aux. cable to listen in my car and i get the same sound through my speakers, but i can twist it a little to one side or the other and it starts to play fine. Anyone got any ideas what may be wrong (shortage, water damage, etc.) Thanks in advance.