We have a 1mbps broadband connection in our office in India connected to our office in Sweden through a vpn box. We have 12 computers running outlook 2003 clients connecting to the exchange server in Sweden. We also have 2 Nortel ip phones connected through the network to Sweden office. The voice on the ip phones gets clipped while going out, whereas the incoming voice is clear and perfectly all right.The phones have been installed recently. What could be the problem?