Fast forward/reverse
It is possible to fast forward/rewind audio and video files[1].
Hold the button for 
/ 
depressed in order to fast forward/rewind audio or video files forward/backward.
Audio files are fast forwarded/rewound at one speed, while video files can be fast forwarded/rewound at several speeds. Repeatedly press the buttons / to increase the fast forward/rewind speed for video files. Release the button to return to viewing at normal speed.