TZ 400 Loopback User X1 Link Down and Up

Anybody seen this before? I have the exact same setup at multiple locations and only this one is giving me this batch of errors 2-3 times a day with about 12 hours in between. I've tried a new cable to X1 and also forcing the connection to Full Duplex. Text Log below also:
12:06:15 Mar 01 998 Users Inform GUI administration session ended 127.0.0.1, X0 0.0.0.0, 0, X0 tcpadmin
12:06:15 Mar 01 261 Users Inform Administrator logged out 127.0.0.1, X0 0.0.0.0, 0, X0 tcp Loopback user logout
12:06:11 Mar 01 566 Network AlertI nterface X1 Link Is Down X1
12:06:09 Mar 01 565 Network Alert Interface X1 Link Is Up X1
Category: Entry Level Firewalls
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Answers
Forgot to mention, X1 is connected to Frontier FIOS Modem/Router (Fiber Optic Internet Service).
@joshuamarius I would suggest to test the connection on another free interface on the firewall to isolate if it is a hardware related.