After setting everything up, I connected a phone and dialed. The called number answered but then I could not hear anything (happened on both calling and recieving parties) - the "mute" button syndrome.
I think there are numerous issues involved and you have to troubleshoot each one to see what works.
I went on the magicjack chat line and went thru a list of the usual things - sent the volume control at 1/3, run this diagnostic program and another one and reboot etc etc to no avail. Ports 5060, 5070 were open already.
I came across some posts the suggested opening up UDP port on the router from 10000 to 65535.
I have Verizon DSL and their Westel modem which I know blocks a lot of Ports and I have my own router which also can block.
I tried opening ports with port forwarding from 10000-65535 on the Verizon Westel and IT WORKED
I don't understand why magicjack needs these high UDP ports open to work. Other website info states that "this should not be - that the firmware needs an upgrade" - however Verizon is not the best place to get this type of support and since it works I stopped looking.
I wonder how many other users of magicjack have literally smashed their devise in frustration. Some lucky users seem to get it to work out of the box.