When NPC walks by he has to look at me, especially when I get very close. But some of them just look other side until I engage into conversation: http://images.pub.goha.ru/files2/mindw0rk/Skyrim/eyes.jpg

Any idea what could cause it? I have huge modlist and no clue about culprit

The odd movement with NPC's eyes are an engine related issue (much like the lip-synch bug) that was introduced with version 1.9 of the Official Skyrim Patch. I would assume that this is probably what you're experiencing from looking at the screenshot.

Could it be mod, or ENB related ???