Why do I get this error (Error event occurred at 15:44:11 for video input object: RGB_640x480-kinect-1. GETDATA timed out before FRAMES were available.)

Hi there; I am using kinect with matlab and in my code I always get this error!

Error using drawnow Error while evaluating uicontrol Callback

Error event occurred at 15:44:11 for video input object: RGB_640x480-kinect-1. GETDATA timed out before FRAMES were available. Error using imaqdevice/getdata (line 149) GETDATA timed out before FRAMES were available.

Error in guikinect>pushbutton3_Callback (line 541) image = getdata(colorVid);

Could anyone help me?Thanks in advance!