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A little back story on the setup first; We have a Cisco VoIP setup at our remote office(where I'm at) and the main CCM/CCX/Unity setup is at the parent company across the US in Connecticut. We have MPLS tunneling the VoIP traffic between the two offices. Very inefficient, but that's the cheap solution they went with to avoid the extra licensing of a second CCM/CCX. Also no one at the company works on the phone system, it is all outsourced to a third party, which stopped responding to my pleas for help a month or so ago.

Anyways, the way it works now, is if you call our 800# it goes to the main Auto-Attendant in Connecticut, and then is routed to our office, with 4 digit dial. If you call our local direct number, it rings through to the receptionist.

So the problem that I need your help with is; I am under a constant attack on my local #. If I leave my phone line plugged in to my VoIP router after 3:30, I will have upwards of 1000 voice mail messages in the morning by 7 am. It basically continues to try and bounce it's calls through our system until the voice mail box is full. I tried working with the tech company managing the system, and they basically came to the conclusion that we need to change our number or unplug the line every night.

The phone company also doesn't seem to know what to do either, I worked with a senior-level tech for a few hours, and he said the return field was being randomly generated/spoofed for each call that came through, so there was really no way for them to block them either.

The messages are usually just a minute or two of "Beep..Beep..Beep..Beep," and also hardly occur at all during the day.

Is there any hope at getting this resolved other than changing the phone number?

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"and also hardly occur at all during the day." This indicates the problem exists while you are at work. –  Ramhound Dec 8 '11 at 17:30
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Could you get the phone company to trace the call to find where it's originating beyond just looking at the return number? –  Steve Dec 8 '11 at 17:44
    
We get the occasional call during the day, but it's not that common maybe once or twice a week between 7 AM and 3:30 PM. I stayed late one night, and around 5 PM the calls would come in every 3 minutes and literally didn't stop until the mail box was full. –  Ian Dec 8 '11 at 17:50
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I find it hard to believe the phone company cannot tell you who is calling you. I would suggest getting that court order. It sounds like they are giving you the run around. I understand the reason changing the number is not an ideal solution, this is a problem that your provide should be able to resolve, I dare say if they cannot then perhaps threating to get a new provider might help. –  Ramhound Dec 8 '11 at 19:38
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@Ian: does the beeping sound like a fax handshake? If so, you could try temporarily forwarding your phone to a fax machine and receiving a few faxes. This won't solve your problem, but it might provide some clues about the caller and his motive. –  Mox Dec 10 '11 at 4:03

1 Answer 1

If you suspect a local device such as a fax machine being unintentionally forwarded, change the id of the device.
If you can recall when this first started, it may shed some light on this. I would look for teleconferencing voip equipment as well.
Why was this listed as fraud -- did you have prior issues with fraudulent calls?
Do you have any disgruntled employees leave the company? Changing vendors due to inadequate support or to an SLA issue is enough to get out if your contract. Sounds like the best way to go if you are remaining calm and collected when dealing with their tech support, etc. Hope that helps...

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