^^ Does the 2 month time period mean anything to you? Has anyone passed that you or your husband knew? Is there any history in your home?
I don't know much about this phenomenon, but it has been happening fairly consistently with my friend who lost her husband on 6/7/06.
I'd look into it. On the flip side though, my future ex-husband worked at a place where the alarm company would ring our house in the middle of the night for a period of time, until we complained about it.