XL2411Z don't work 4 buttons on screen menu, help.

[ctacx3]

I'm bought this monitor four days ago. At first everything was fine.
Today, stopped working four buttons on-screen menu.It operates power button and one of the five menu buttons (the second of the power button). All buttons work when they hold ten seconds, a message appears on the screen locking and unlocking, but the menu of the monitor they are not working. Works only one with the image settings, I can not move through the items and leave the menu until it disappears by itself. Today, set up the monitor with your utility, buttons stopped working suddenly.

Sry for my bad english, pls help.

[ctacx3]

In support of BenQ said that you need to contact the service center for repair. In the store two weeks later issued a new monitor.
Probably faulty control board.