Strange shift key behaviour when renaming files in ubuntu

There is a really puzzling behaviour in Nautilus regarding my Shift key. Consider the following scenario: 1. Choose any file to rename
2. During renaming i can type just fine unless i need a capital letter. If i type a capital letter (using shift) then focus shifts to some file at the same folder.

Clarification: Current shortcut to change layout LShift+RShift.

Solution: Change shortcut to, for example, LCtrl + LShift (System Settings -> Text Entry)and the problem disappears.