I upgraded my virus subscription…PC-cillin. I removed PC-cillin, still no good. I then removed both PP 1.5 and PP 2.0. I reinstalled 2.0 only, without PP 1.5, still choppy. I removed the OHCI firewire card, tried the firewire port on my Audigy sound card. I’m about ready to format the drive, keep my project and captured clips on another dedicated drive, and start over. Are there limitations on how many times I can reinstall and activate PP 2.0? Any help would be appreciated.