Need help! Can call but no hear

[whirly]

I can make calls to my Magic Jack from my landline & cell phone and visa versa from my Magic Jack. I can hear a dial tone from my Magic Jack, but that is about it.... I can not hear any ringing or anyone answering from the other end. All I can do is call & ring their phone.

I am using a telephone and have upgraded the latest Mac version. I am using Snow Leopard, Mac OS X 10.6.4

Appreciate any advice