Problem receiving calls. My X-Lite works fine on outgoing calls but if someone calls me it rings on my computer and I anwer but their telephone just keeps ringing until the answerphone picks up the call . It was suggested that my router was the problem so I opened all the ports required , set up a static IP address and made sure my firewall wasn't blocking anything all to no avail . Has anybody out there sorted this problem and if so how? Please help.