I edit HDV mostly, which plays smoothly in my system. The only time when it doesn't is when I'm playing the timeline and the cursor reaches the end of the current view so it shows the next segment and is starts to render the thumbnails. Each time it renders a thumbnail the playback freezes for a split second, which I find very annoying. Is there a way to force Vegas to show only the first and last frame of each event, rather than all of them? I know that I can choose not to display waveforms and frames, but it's useful to have at least the first and last frame of an event, and the waveforms always to do volume envelopes.