1) Make Editable in the Functions menu or in the contextual menus if you right-click on the object in the editing window or theOM, Make Object Editable in the toolbar on the left or with the object selected hit the ‘C’ key.
2) if you are following his tutorial the spline effector should have Segment Mode (in the Effector tab) be set to Even Spacing or Random because a text spline is a multisegment spline unlike his example circle
3) if you have Scrub Sound in the Sound Effector checked off then you just need to enable Play Sound in the Animation menu