Problem #1: Have you tried disabling the Auto-Answer/Receive option when using the phone?
Problem #2: Have you tried adjusting the number of rings between the time the answering machine picks up, and the number of rings before the Fax picks up? It's highly likely that both the answering machine has the adjustment, and I know the fax machine does, so you might try going into the menu to see if you can get the desired result by either adding more rings to the fax machine, or less to the answering machine.
I know I'm not the only one with this problem:
Environment: Vonage, TimeWarnerCable RoadRunner, Uniden DECT2.0 Phone system w/answering machine, Samsung SCX-4826FN printer/scan/copier/fax.
Problem #1: When talking on the Uniden phone via Vonage, the fax machine will randomly pick up and act like it is trying to receive a fax. This is quite annoying because only the other party hears the fax tone. We are still talking on this end of the phone and only when the other party doesn't speak, do we realize that we're disconnected.
Problem #2: When someone calls our Vonage number and the answering machine picks up the phone, the Samsung fax immediately tries to receive a fax. However, the problem is that the incoming call is a voice call, not a fax. This is bad because no one can leave a message on our answering machine when we're not home!
Anyone have any solutions to this? If no solutions, then my only real option is to get another dedicated fax line which costs $$$.
Thanks for your help!