Clifford Matrix RS III wiring

Alarm system is a matrix RSIII (3) and the car is a 1996 monte carlo.

 When I arm the car, sometimes I get a second notification(beep) in my remote and the hammer icon and the number 1 and 2 blink in the remote. Whenever this happens I would go ahead and disarm and re-arm the alarm and I would not get a notification. Right now is getting to a point where is kinda frustrating to do this every so often. Any ideas on what could it be? I have a 506T sensor hooked up as well as the shock sensor. I did test both of the sensors when I was done with the install. They would report the correct zones, and the sensor numbers in the remote are 1(shock sensor) and 2 (glass break),so they must be hooked up correctly.

The only thing I can think of is that evrytime I arm the alarm, the parking lights flash once and  my car  senses that the parking lights are on for that instant making a bell sound from a OEM speaker inside the car. But I have never had a problem with this before. This is a second alarm in my car and both have had the 506T sensor in it at the same location.

Isn't the 506T supposed to wait 3 seconds after arming to start monitoring? The bell sound does not sound longet than 3 seconds. Anybody has an idea of what could cause this? My brain is not comming up with any answers.