Here is one I am stumped on.
We have a Dell 1815 Multi-function with fax. It used to be hooked up to Vonage and worked fine both incoming and outgoing. Now we have it hooked up to a analog line and it works fine for everything except faxing to one recipient. If I plug it into a second analog line it still doesn’t work. As soon as I switch it back to Vonage it works fine. A different 1815 was hooked up and it did the same thing.
When I monitor the line I hear the 1815 call the number and put out tone. When the recipient number picks up it just goes dead. On Vonage the recipient fax talks back and everything proceeds normally.
My question is what could be going on with the Analog lines that would make just these two faxes not talk to one another?