Need help troubleshooting non-unRaid problem

I have two unRaid servers and both are running apcupsd.  I only have one UPS, so Tower2 communicates with the UPS through Tower1 via the "Network Information Server" that is enabled on the apcupsd running on Tower1.  Everything seems to work perfectly except I get a lot of the following lines in the syslog for Tower2:

Nov 11 22:33:26 Tower2 apcupsd[2390]: Communications with UPS lost.
Nov 11 22:33:26 Tower2 apcupsd[2390]: Communications with UPS restored.
Nov 12 04:34:14 Tower2 apcupsd[2390]: Communications with UPS lost.
Nov 12 04:34:24 Tower2 apcupsd[2390]: Communications with UPS restored.
Nov 12 04:52:25 Tower2 apcupsd[2390]: Communications with UPS lost.
Nov 12 04:52:28 Tower2 apcupsd[2390]: Communications with UPS restored.
Nov 13 04:41:44 Tower2 apcupsd[2390]: Communications with UPS lost.
Nov 13 04:41:47 Tower2 apcupsd[2390]: Communications with UPS restored.
Nov 13 04:51:37 Tower2 apcupsd[2390]: Communications with UPS lost.
Nov 13 04:51:42 Tower2 apcupsd[2390]: Communications with UPS restored.
Nov 13 04:52:39 Tower2 apcupsd[2390]: Communications with UPS lost.
Nov 13 04:52:43 Tower2 apcupsd[2390]: Communications with UPS restored.
Nov 13 04:53:51 Tower2 apcupsd[2390]: Communications with UPS lost.
Nov 13 04:53:53 Tower2 apcupsd[2390]: Communications with UPS restored.
Nov 13 04:55:57 Tower2 apcupsd[2390]: Communications with UPS lost.
Nov 13 04:55:58 Tower2 apcupsd[2390]: Communications with UPS restored.
Nov 13 22:01:46 Tower2 apcupsd[2390]: Communications with UPS lost.
Nov 13 22:01:51 Tower2 apcupsd[2390]: Communications with UPS restored.

There are no relevant or corresponding lines in the syslog for Tower1 at or around the same time.  It will sometimes go days without a loss of communication, and then it will flare up like above.  I can't seem to find any pattern or tie it to any event.  I'm at a loss on how to begin troubleshooting this.  Anyone have some suggestions?