I am running BTV 4.0 and at times the audio will stutter when I am replaying recorder shows. I believe this may be due to my harddrive being fragmented. I have tried the installed windows defragmenter, as well as the defragmenter in System Mechanic 6. The map in both defragmenters appear to show plenty of open space to move files around in order to defragment the drive, but there are usually a couple of files that neither program will defragment (usually movies or some other longer show.) Is there a defragmenter program that will work better, or any other suggestions why my audio would stutter? I am using an IAW video card, and I know there are issues with the software coding versus hardware, but my impression is that those issues are mostly video not audio.