I tried a tip i got from the forums and went into the controls in Sony Vegas 11 and turned off the use of the vid card processors and just use the CPU for rendering, No more problems with color bombs, also rendering times went up. If I remember correctly the problem started when I let Nvidia update the the drivers for my card. I may go and remove the drivers and replace them with the original drivers and test thing again. I will post an update when the testis done
