AT&T should be able to replace it for free, and the latest 8310 OS is 4.5.0.99 from Vodafone. I think the OS would fix memory issues (if any), maybe help your battery last longer. Stuff like that. Sorry I couldn't be a complete help, but I don't know much about the 8310.
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I think even out of warranty they should replace it. I mean I bought my 8330 used from eBay, and Sprint always replaces my trackball with no questions asked.
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Yea it sat in storage in a warehouse for 6 months so i'm sure there was some moisture issues...or just bumped around in the move...it works flawlessly except for the trackball
Yeah, that's probably the problem. Well you can ask people at AT&T if they can clean the inside of where the trackball is at. My trackball was just like yours, but I could click with the trackball I just had to do it hard. I took it to Sprint, they clean it and it worked brand new.
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