Curtis DPF828 - Manual (Page 5)

(5) Left: In background audio files or video mode, press it to turn up the
volume
(6) Down: In background audio files or video mode, press it to go back to
the next track
(7) Function: Press and hold down this key to set up through the menu
(8) SD/MMC/MS card’s interface
(9) USB Host’s interface
(10) DC In interface
Remote Control