The screen froze and keypad just wouldn't work. How to restore it?
1 Turn off your player.
2 Press and hold the Play/Pause.Continue to hold the Play/Pause button until you perform Steps 3 and 4.If you accidentally release the button, start the procedure again.
3 Gently push the end of a thin object (like a pin or straightened paperclip) into the Reset hole. The reset button for the ZEN Mozaic is located on the left side of the player, with the menu buttons facing you.
4 Slide the On/Off/Lock switch towards the power button and hold until the display lights up. The Recovery Mode screen appears, and four menu items are shown: Clean Up, Format All, Reload Firmware and Reboot.
From here you should be able to choose to reload the firmware.