The issue that you are experiencing points to a bad battery.
There is a backup battery in the control box which does wear out with time, and will need to be replaced.
Find the master control box, usually a gray or tan metal box and usually located in a pantry or closet, and open it up.
You'll see a battery there which can be removed with 2 quick connect plugs. Pull that out and replace with a new one like this: http://amzn.to/2duGmY1
In the meantime if the sound is too annoying, you can disconnect the battery and pull the main power plug to shut the system down completely until you can get the battery replace.
If you have any other questions, just let me know. Otherwise, please take a moment to rate my service using the stars at the top of the page; hopefully I have earned 5 Stars. I also invite you to contact me directly with any future support needs at http://bit.ly/1QwLxGh and ask for Nathan.
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