cocos2d-x 3.0 alpha, warning sound on mac10.9 when keyboard pressed.

cocos2d-x C++
#1

I am working a game for mac on Mac 10.9 mavericks use cocos2d-x 3.0 and need keyboard input.
I get key event by function Layer::keyPressed(int keyCode). It’s working, but mac playing the warning sound like “Dong! Dong! Dong!” when I press the key.
Build Environment: xcode 5.0

How can I fix this? Is it a bug or only my mac mini meets this?
I don’t have the mac 10.8 environment.

#2

It’s working with no warning sound when I comment [super keyDown:theEvent] in function -(void)keyDown:(NSEvent*)theEvent and function keyUp of file EGLView.mm.