osx - Cursor is moving too slowly in Xcode -

I am using 'XCode 4.3.2'. Increasing the carat is so slow that when I need to reach the given space on the screen, I'm compelled to use the mouse.

Other applications normally behave. I keyboard sensitivity is set at maximum speed in XCode, it takes 10 seconds for 70 seconds to go; In TextEdit, it takes 2.5 seconds.

It seems that it is related to relevant help.

Is this a known problem in XCode, and is there a way to resolve it?

This is where XCode has many open projects.