Veritas 8 noise?

Hi,

We have a Veritas 8 house alarm installed in the house by previous owners. We've never used it since we had it serviced 3 years ago.

My question is: If there is something wrong with the system, can it make a penetrating high frequency sound audible only at night when the nearby road and the house itself are quieter? We have been experiencing this penetrating sound impossible to deaden even by earplugs and are trying to eliminate the causes of it. Although we turned the power off everywhere in the house, the sound remains, and the alarm then works on a battery.

I would be really grateful if you could let me know if Veritas 8 could be the cause of that if it developed a fault.