Answer to: Why doesnt my iPod play with headphonesCould be something in the jack. Does headphone plug go all the way in and then click? can you see shiny white indicator at bottom of jack? Try blasting lint or other debris from jack with compressed air. Be careful to hold can upright so as not to spray condensed moisture into ipod!
Answer to: headphones connector sound in one ear onlyA common problem. It's either just a bad set of headphones (best case) or the headphone jack in the ipod is damaged. One of the contacts could have been bent so that it no longer connects with the plug. If you are like many people, you may leave your headphones connected to your ipod when you store it in your pocket or a bag. Pressure on the base of the plug can force the tip of the plug into one side of the inside of the jack, deforming it. I don't know of any way to fix the jack, but it is a cheap part and is easy to replace.