Update:  phone calls continue to be a nuisance (even over the weekend).  Agree that it does sound like it's a fax because it just beeps.  Received another call last night at 3:30 am (EST) and again this morning at 9:00 am (EST). I have called the # back and it's a voicemail box.  Left a message demanding they stop calling.  I called Verizon this a.m. to report it and they also left a message on the voicemail box and said give it 48 hrs and if the calls don't stop they'll put a trace on the #.

Fax machine from Orange County CA in the middle of the night EST

Phone have been coming for the past few weeks, several times a day, all hours of the day and night