Continuous Scrolling During Playback(Pro Tools HD and Pro Tools with Complete Production Toolkit Only)When this scrolling option is selected, the Edit window’s contents scroll continuously past the playback cursor, which remains in the center of the window. With this option, playback is always based on the Timeline selection (unlike the Center Playhead Scrolling option). Continuous Scrolling During Playback uses host processing power, so use this option with host-based Pro Tools systems only when absolutely necessary.