BB 8520 Trackpad Freezing (need to lock and unlock to resume)
 

I have had issues with a blackberry trackpad and was taken for repair, the first attempt was a new trackpad which still froze in menus when scrolling, an IC was replaced and after this it seemed to be working fine for a couple of months, now all of a sudden it seems to be getting worse and is now freezing again but sometimes I can use for many hours and is fine, but now getting worse, I need to lock then unlock the phone to get it to unfreeze but before i actually had to take the battery out and reinsert.

anyone any idea what could be causing this?

thanks in advance.