If it happening under GB, it might be a hardware issue then. Won't hurt to play.
3 years is good life for a smart phone. With security a major focus, the P970 is a little old.
Yea it seems like a hardware issue only. It was great having such...
EDIT: Did this happen before you upgraded to ICS, or after? ICS has a ROM bug, both on factory and custom; the bug causes a loss of touch control. Going back to GB makes it go away.
I ran GB-based custom ROMs and eagerly updated to ICS-based ones...