So, I've got an X-52. Not the pro model, just the plain old grey one. But the sticks developed a bit of a squeak at times. I know that the piece making the noise is the plastic ring at the bottom of the spring.
It only does it during slow movements towards the edges of the joysticks movement range.
My first reaction was to google the problem, which came up with two choices. Silicon spray, and chap stick.
From what I've read, the silicon spray actually made the squeak worse, but the chap stick helped. Anyone else ever had this problem? I've tried also just cleaning off the plastic ring, but that only helps for a few minutes.