When you select a sound layer in the Timeline view, the options related to that layer appear in the Layer Properties view.
If you double-click on a sound layer in the Timeline view, or in a sound column in the Xsheet view, the Sound Element Editor dialog will open. This dialog allows you to fine-tune the sound track's lip sync, start time, stop time and volume.
NOTE Contrary to all other layers, sound layers are not represented by nodes in the Node view.