Hope someone can help. Installed an IPK2 with a VMP-U40 VOIP card. Programmed card as Meggaco MG16. Using dTerm 32-button phones with IP-R adapters. Have switch in main office with 3 satelite sites. Using IP phones at the 3 sites. Phones at each site can call the main office and vise versa with no trouble. Phones at each site can call a phone at the same site with no problem. Phone at one site can call the DID line at another site or call the auto attendant and be transferred to another site with no problem. Trouble is when a phone at site 1 calls the three digit extention of a phone at another site phone says calling and the DSS button for both phones lite up. The phone at the other end rings and says Calling from The extention. When the phone answers both phones say talking but their is no audio on either phone. Only happens when one remote site calls another. I am totally stumped.