sound thru only one earbud.

My iPod only plays music thru one earbud. i've tried numerous earbuds and it's the same with all. so i've come to the conclusion that it is the iPod at fault. i'm considering buying a replacement headphone jack from this site. but what i've noticed from the one this site sells and from others is, that the others have the actual "jack" that gets the earbud pin put in. after lookin at the picture for the one this site sells, i can't see the actual jack on one end of the whole thing. it just ends with the ribbon. should i not buy this one but a different one with a jack on the end?..or will this one without the actual jack on one end fix my problem? thank you.