PAC sending commands when it should not

I have customer that has been working well for years..
Doorbell switch in input modules and two door bells on output module.

ONLY pac code is

once (GetLightingState("Door Bell Button") = ON) then
begin
PulseCBusLevel("Local Network", "Lighting", "Door Bell House", 100%, 0, "0:00:01", 0%);
PulseCBusLevel("Local Network", "Lighting", "Door Bell WorkShop", 100%, 0, "0:00:05", 0%);
end;


door bell has been recently been going off for no reason.

I have been logging the cbus traffic....

normal Operation

DateTime= 8/08/2020 2:49:00 PM App= 056 Lighting Group= 053 Door Bell Button Unit= 215 Event= Group on
DateTime= 8/08/2020 2:49:01 PM App= 056 Lighting Group= 046 Door Bell House Unit= 250 Event= Group on
DateTime= 8/08/2020 2:49:01 PM App= 056 Lighting Group= 047 Door Bell Workshop Unit= 250 Event= Group on
DateTime= 8/08/2020 2:49:01 PM App= 056 Lighting Group= 053 Door Bell Button Unit= 215 Event= Group off
DateTime= 8/08/2020 2:49:02 PM App= 056 Lighting Group= 046 Door Bell House Unit= 250 Event= Group off
DateTime= 8/08/2020 2:49:06 PM App= 056 Lighting Group= 047 Door Bell Workshop Unit= 250 Event= Group off


but when the phantom door bell happens i see this

DateTime= 22/08/2020 7:59:48 AM App= 056 Lighting Group= 067 Family Room TV Unit= 250 Event= Group off
DateTime= 22/08/2020 8:00:54 AM App= 056 Lighting Group= 052 Garage Front Light Unit= 250 Event= Group off
DateTime= 22/08/2020 8:00:54 AM App= 056 Lighting Group= 046 Door Bell House Unit= 250 Event= Group on
DateTime= 22/08/2020 8:00:54 AM App= 056 Lighting Group= 047 Door Bell Workshop Unit= 250 Event= Group on
DateTime= 22/08/2020 8:00:56 AM App= 056 Lighting Group= 046 Door Bell House Unit= 250 Event= Group off
DateTime= 22/08/2020 8:01:00 AM App= 056 Lighting Group= 047 Door Bell Workshop Unit= 250 Event= Group off

or

DateTime= 22/08/2020 10:48:23 AM App= 056 Lighting Group= 046 Door Bell House Unit= 250 Event= Group on
DateTime= 22/08/2020 10:48:23 AM App= 056 Lighting Group= 047 Door Bell Workshop Unit= 250 Event= Group on
DateTime= 22/08/2020 10:48:24 AM App= 056 Lighting Group= 046 Door Bell House Unit= 250 Event= Group off
DateTime= 22/08/2020 10:48:28 AM App= 056 Lighting Group= 047 Door Bell Workshop Unit= 250

Unit 250 is the PAC

there is NO "Door Bell Button" event so why is the pac sending the pulse commands.

any one else seen this sort of thing and have any ideas ??

do PAC do this when they get old ??

 

My guess is that it isnt the PAC but the output unit, its a thing that happens especially on older units, I KNOW it says its unit 250 but basically the output unit 'mirrors' packets that have come in and transmits them later. Are the channels with the TV Unit and the Garage light on the same output unit as the Doorbells? If so, I would try replacing or isolating that output unit for now and see if that fixes the erroneous messages.

 

Thanks for the response the door bells are on a NEW 24V relay module may be there is a power supply failing...