MCC5500/APX/ACIM ID issue...

[Smac61]

Just finished hooking up 2 APX consolettes to an MCC 5500 on a DAP I Digital circuit / ACIM data connection.
Everything is working fine except every so often random ID's pop up in the channel window.
They always pop up 3 in a row with the same time stamp.
They do not appear to be active id's on the system.

Que looks like this: (aliased ID's are legit traffic)

CAR 80_______15:36:45
P336_________15:36:05
10107113_____15:10:02
10107113_____15:10:02
10107113_____15:10:02
CAR 82_______14:53:27
DISPATCH_____14:52:54
CAR 82_______14:52:20
DISPATCH_____14:51:54
10103542_____14:42:37
10103542_____14:42:37
10103542_____14:42:37

Any thoughts?
Thanks.