DirectRT using 100% of CPU?

Hi, I'm setting up an experiment in which 1 instance of DirectRT is called from MediaLab. Sometimes, when MediaLab calls DirectRT, the computer stalls and the task manager indicates that DirectRT is using 99% of the CPU.

All of my computers are the same model with the same RAM, but I only have this problem on certain computers. Any ideas why this might be happening and how I can fix it? Thanks!!

Are the versions of MediaLab and DirectRT the same on all your machines (i.e., 200x.x.x)? If so, how reliable is the problem on the machines where it happens (e.g., [I]x [/I]out of 10 times)?