The dial out. The problem is sometimes those phone systems need an analog line. If you are using a cheap Voip or the bandwidth fluctuates then your system will have a problem calling out. I had a problem with an alarm system using a VOIP line. It would dial connect but the handshake was the problem. Then one of the credit card machines couldn't dial. I told the IT guy what the problem was he said it was BS. So I told him that the system is working I swapped it with a new one and it is now doing the same thing so the BS is now your problem!
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