Cross DJ with video plugg in Hardware acceleration problem

Hi
I use a AMD phenom II X4 820 (quad core) 2,8GHz 8GB ram with Windows 7 64bit. My graphic card is nVidia GeForce GT 230
The problem I have is that when playing 1 video the CPU runs up to 55% on alle 4 cores, when adding 1 more video to mix the CPU runs up to 100% on all 4 cores. It does not seem to be using my nVidia graphic card. Can not find the option to turn on hardware acceleration.
Any help or tips on this would be helpfull.
I use a AMD phenom II X4 820 (quad core) 2,8GHz 8GB ram with Windows 7 64bit. My graphic card is nVidia GeForce GT 230
The problem I have is that when playing 1 video the CPU runs up to 55% on alle 4 cores, when adding 1 more video to mix the CPU runs up to 100% on all 4 cores. It does not seem to be using my nVidia graphic card. Can not find the option to turn on hardware acceleration.
Any help or tips on this would be helpfull.