Kinect simulink to NXT Run On Target Hardware

hello. i'm running an experiment using 2 computers, the 1st computer is running a simulink model that is acquiring data from kinect sensor ,and sends it via UDP_SEND_BLOCK to the 2nd computer. the 2nd computer is running a simulink model that receives the data via UDP_RECEIVE_BLOCK and shows it on a scope. everything works fine when i only receive the data and show it on a scope in the 2nd computer, but the problem occurs when using UDP and run_on_targer_hardware at the same time while connecting the NXT robot to the 2nd computer ,to send that data to the NXT brick.

 it works fine when running the NXT robot using run_on_target_hardware on 2nd computer alone without UDP.

i'm using the USB cable to send data to the NXT brick ,and bluetooth for feedback from the brick to the computer. ------------- MATLAB Version: 8.1.0.604 (R2013a) Operating System: Microsoft Windows 7 Version 6.1 (Build 7601: Service Pack 1) Java Version: Java 1.6.0_17-b04 with Sun Microsystems Inc. Java HotSpot™ 64-Bit Server VM mixed mode.