The joystick does seem to stick a little on moving left or right. I'm not sure what to attribute that to. Also, volume on video files seems really low.
Have you tried to hold the stick like you would hold a screw and turn it slowly counter-clockwise a few times? Of course, this is from "UNFOUNDED" sources, it seems to have pretty good "RUMORED" success rate because it'll loosen up the over-tighten screws.
After reading lots of those "UNFOUNDED RUMORS", I'm getting to realize that GP2x is going to be a whole new beast to me. I mean, with DS or PSP, I won't ever try to open them up that would result in void warrantee. With GP2x, I'm already very tempted to open it up and have some fun, or fix whatever hardware I may face. I'm even considering to replace the red LED to blue LED. The whole thing reminds me of toys (or radios) that I destroyed when I was a little boy who had no idea what he was doing, but was having lots of fun.
Since we're talking about replacing existing crap-tastic firmware with whatever cool thing to come, having some fun with the hardware itself won't be too far fetched idea. That way, GP2x becomes truely open-source/open-hardware.