What should I do if my headphone jack wont let my headphones play music unless you move it constantly

Apple headphone jacks require quite a bit of force to insert fully. Make sure you're pushing the plug all the way in.

Otherwise, you can test the iPod jack by trying it with different headphones. And check your your headphones by using them with other devices.

I recently had a problem with the jack as well. It kept popping out and wouldn't work! It turns out that everytime I was putting the iPod in my pocket, it was getting lint crammed in the port. Crazy, but I was able to fish it out and all is well.