When I return home, after setting my home alarm system, the speaker on my phone comes on and then I hear a loud busy tone from my phone. It appears that my phone is hooked up somewhere with my alarm system. It also appears that if I do not cut my alarm off in time, this may interfere with the central office contacting me through the phone system. And sometimes, it appear that my phone is tapped or connected to 313-059-4744 --a possible 1st dial--even before the alarm system goes off and may eliminate dial tone for connecting to the central alarm office.