Información sacada de otro foro (click):
Did you try my suggestion to double-check the remote codes? There is a tiny switch located on the bottom right hand face of the remote, underneath the sliding cover. It has positions for 1, 2 and 3. The normal code of the recorder when you buy it new is 3, so make sure the switch on the remote is set to 3.
En cristiano: Comprueba que el botón de abajo del todo en la parte derecha debajo de la tapa no se ha movido...