TL-150 general supervisory errors?

[Tower Security <regsiemens@xxxxxxxxxxx>]

Recently installed a TL-150 (IP module) on a DSC PC5010 and while it
transmits codes properly,  we're getting recurring General System
Supervisory troubles that seem to happen on the hour.  Might skip an
hour or two but if it happens, it's always on the hour.  Network
supervision is not enabled.  Things we've tried so far:

Power cycling the TL-150
Changing the test frequency (currently set to 99 i.e. ~24 hours)
Assigning a fixed IP address
Making sure port 3061 is open on the router
Disabled provisioning on the router

Nothing has helped.  Another weird scenario is that when you log onto
the TL-150 while in trouble, and look at the status, it displays zones
as being open that are not assigned or defined i.e. zones above what
are enabled e.g. 18, 24 (when only 16 zones exist).  I've checked
programming and Zone assignment and definitions are definitely not
setup for either partition...fwiw it's not even a partitioned system.

I've called tech support and they think it's the router resetting the
IP address but enabling a router log shows nothing odd.  I feel it's
gotta be panel related as the Supervisory trouble always happens
exactly on the hour.  The router has no internal clock and it's too
coincidental that the panel and router would be in perfect synch time
wise.

Any ideas?

Thanks,
Reg Siemens
Tower Security Systems Inc.