Default Bizarre screen behavior

Hi, i have noticed a strange screen behavior.
My Atrix is an international version, Rom is Epinter cm10.1 with kernel 3.1 (kernel-2014_02_23_08_58).
Sometimes when i trying to write some message, strange screen behavior makes the letters themselves appear / press.
Lock and unlock then, will fix it temporarily.
What is wrong ?

CM9 - OK (no screen problems)
Atrics 2.0 - OK (no screen problems)
Except the known problems of kernel 3.1

Sorry for my poor english.
Im from Poland. Is there anyone here who could translate (if my english will be too weak ) ?