Reply to Cpu spikes in traktor!!!!!!

I have just upgraded to Windows 7 and everything has been working fine but after playing at home for 30 mins i start to get 100% CPU spikes which effects the sound and slows the tracks down. I am using the new mapping with traktor 1.2.4 and VCI100 FW1.3. Has anyone else experienced this? and how can i sort it out?