I was going to recommend the exact same things as ginsu, but maybe before shelling out the extra dough...just to see, maybe do quick easy testing. Be sure that you are playing these games with the stick programmed to 4-way mode and nothing else. If that doesn't do it...try the restrictor and springs, then lastly there is the slight possibility that your pcb is damaged as you stated earlier. If you get the spring and restrictor, you will not be disappointed, it makes the sticks feel really nice.
Yea guys, he needs to do a little map testing before going nuts. He stated in his second post that he is not 100% sure what mode the stick is in...