Mine has phantom key presses too, I have reset it twice.  Right now it seems to be working fine, but last time I reset it..after a while it would start doing it again. Mainly it keeps putting uuuuuuuu and I can't touch the back button because it will bring up the tabs screen.  Frustrating at times..I usually just turn the screen off and back on for a temporary fix.

Hoping the 5.0 update fixes it