What exactly? Does it feel stuck when scrolling? Like the ball's rolling but it doesn't make the scrolling noise? I'm not talking about the sound setting. You can actually hear and feel if the ball is rolling on the sensors. So I guess it's a whole new trackball assembly. Not just the ball. I had that problem. I made it way better by rubbing a damp bounty with alcohol repeatedly on the trackball. This caused the ball to roll and clean the rolling sensors. But if you got the whole trackball assembly, it may be the sensors on the motherboard. I wouldn't know about that stuff. You could try cleaning that part once you open up the phone but I'd much rather wait and hear what others with more experience say first before trying it.
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