My headphone jack broke on me a few weeks ago, it is not rattling around, but it does not work. I tried 5 different pairs of headphones, none of them worked. Because I bought the GP2x as a media player, this is bad. I sent an email to GP32z asking for some sort of repair or return, but they did not respond. I don't mind fixing it myself, I am decent with a soldering iron. Is there some sort of established way of fixing the headphone jack? I guess I want the experiences of people who have done it before.

it's really simple, there are 4 contacts total I believe, just re-solder them over the old solder. It'll work perfectly, and it's pretty much self-explanitory. Just open it up and you can see it.

The same sort of thing happened to me, luckily its really easy to fix. You just unscrew the gp2x, and solder the headphone socket back on to the matching terminals which are below the hole for the headphones, simple as that.
If youre still worried about doing it a detailed guide is here:
http://www.gp32x.com/board/index.php?showtopic=24004

Thanks, that is exactly what I was looking for.

GP32z is sometimes (Most of the time) slow with email replies, but he will surely replace/fix it for you if you cannot get it running.

The problem I have with my headphone socket is that I have to hold the headphone jack in place to get stereo sound -- if I don't I only get audio in the left ear. It's really irratating trying to hold it in the right position while watching a video/listening to music and impossible when playing a game that requires two hands.

Do you think resoldering would fix this problem? I opened my GP2X up and looked at the 4 solder points for the headphones, and they all seem to be attached ok. I've also tried 3 sets of headphones and all had this problem, so I'm sure its the GP2X. Any suggestions what to do to fix it?

I guess adding an extra blob of solder would never hurt (unless u solder 2 connections together ) It sounds like if connections arent being made cleanly if u have to push in the headphone jack, so that would be your bet bet.
If that doesnt work all u can do is send it back.