I recommended VOIPo to a friend and he got his adapter two days back. I have never had any problem with VOIPo till now and my friend also doesn't have any problem calling any other number, but whenever we call each other, the phone rings but there is no audio. We both called support and were told the same thing - to forward ports 5060-5080 and 35000-65000 - and we did, but the problem still remains. I'm going to call support again but was wondering if anyone has faced a similar issue and got it resolved already.