ESPRIT FALSE ALARM

["proguard" <spkintz@xxxxxxxxxxxx>]

I' ve got an old Paradox Esprit 728 v 1.0 default and installed in one
of my clients house.
It is monitored also from my ARC and untill yesterday all the previous
3 years works fine.
Now we monitor alarm signals from zone 4 (first) and second from zone
1. Z4 is a PIR and Z1 is an aleph m.c. in the entrance door. All the
alarms came from Z4,Z1 with this sequence.
I don't know what causes the alarm but the motion detector is just
fine, the same the m.c.
I believe it must has to do with the resistor for the zone doubling. I
use common resistors from the market and not those provided by
Paradox....

Anyone idea what cause this alarm?!?! (Z4, Z1)

Thanks in advance!

Spyros Kintzonides
Greece