External siren attack possible?

I have just watched a vid on Youtube where a guy removed the external siren from the baseplate and it produced a notification but the alarm did not go off. The alarm appeared to be in the Alert state as the Dusk to Dawn feature was lit.

Is this correct - the external siren can be taken away and the alarm does not go off ?

Hi @Mike077. Would you be able to share the link to the YouTube video? This will give me a better idea of what happened. I can give a better answer once I know all the facts.