Im getting a lot of phantom calling to Rooms I have 5 rooms that get phantom calls. I have replaced the Jacks for the entire property and I have dial tone at for all of the phones. I can call the console with all the phones. Usually when I've had a phantom calling issue it was a bad phone. Any tips for finding the source or sources of the calls?

AA problem? Call forwarding set up somewhere that shouldn't be? Some line(s) set for DIL in 'NIGHT' (or 'DAY'). Make sure these 5 rooms are not in hunt group or ring group. I had a call that a room was unrentable, because it got calls from 5A to 8A. System had been moved from another motel that had a W/U announcer.(In the SX50, if you select the 'intercept to RAD' option, calls go to 1st analog port in system, PERIOD) That had not been eliminated, but the port had been re-used for a room.

You being in Florida, I'd bet dollars to Donuts that salt air has corroded a cable somewhere.

Had a similar problem and I had to train the night clerks to go and look at the cards in the switch and note which if any of the lights were flashing. I found a jack corroded in a room. Light on card would flash as if it were being pulsed by an old dial type phone.
I also had an SX50 where different rooms started getting calls for wakeups instead of the RAD that was on the first analog port. This has happend several times. Deprogram first port as a RAD and reprogram it fixes it every time.
Just a few ideas. Hope it helps.