Shuttle Lock mode lets you use the numeric key-pad to shuttle up to two tracks forward or backwards at specific speeds: 5 is normal speed, numbers from 6 up to 9 provide increasingly faster fast-forward speeds, and numbers from 4 down to 1 provide progressively faster rewind speeds (4 is the slowest rewind Shuttle Lock speed, 1 is the fastest). If multiple tracks are selected, only the first two tracks are shuttled.1 With Pro Tools HD, make sure the Operation preference for Numeric Keypad mode is not set to Shuttle (see Operation Preferences).2 With the Selector tool, click in the track where you want playback to begin. To shuttle on two tracks, Shift-click in a second track.3 Press the Start key (Windows) or Control (Mac) and a number on the numeric keypad: 0–9 (9 is fastest, 5 is normal speed, and 0 stops shuttling).Once Shuttle Lock mode is initiated, Fast Forward and Rewind become highlighted in the Transport window.4 Press additional keys to change the playback speed, or press Plus (+) or Minus (–) to switch the playback direction (plus for forward, minus for backward).5 To stop playback, press Start+0 (Windows) or Control+0 (Mac).