Hi, how are you setting the alarm? Are you omitting the zone where the dog is or are you part setting, ie using 2+enter+code?
If you are omitting a zone this cannot be silent, but part setting can be. I don’t know how your system is programmed, but it can be programmed to remove the zone you require off and also set silently. Can’t tell you how in an open forum but manuals readily available for your system. The system is a 9448, the 9427 refers to the keypad. Hope this helps.
Alan mckenzie
January 2019