Our FIOS on-line call record shows an outgoing call made when no one was home. In calling that number, heard strange intermittent tones, but not a FAX warble. Googled the number online and found it was a toll-free business fax line but no other information available. When I clicked on Call that number, it appeared that nothing happened, but then it showed up as an outgoing call made -- again with no one home! How is this possible and how can it be avoided? Definitely strange.