SANDISK player malfunction

hi cud any1 tell me how i can reset my sandisk music player?

when  u turn it on it doesnt allow me to go to the menu and its freezed throughout …

http://forums.sandisk.com/t5/User-guides-Firmware-Software/User-Manuals-for-all-Sansa-Products/m-p/185344/highlight/true#M3628