scantronic 9427 keypad sounder?

Hi all, I have install a 9427 keypad to a 9448+panel
every thing seen's working fine ,But when the alarm go's off only the 9448 panel internal sounds & nothing from the 9427 keypad, keypad sounds when i press the keys & to set alarm etc..so please can someone tell me should the 9427 keypad sound's go's off like the main panel when the alarm go's off thanks.
the external bell is ok.