Hi, After a lot of emails to China, typically one per day/night due the time difference, Fanvil believes this problem to be with FreeSwitch. I am quite skeptical; my money is on you guys. Here is the scenario: Phone A is registered to ext 101. It also has a BLF for ext 102. Phone B is registered to 102. Almost everything works exactly as expected. When phone B gets or makes a call the BLF works. The thing that fails is ONLY when phone B calls phone A. At the end of the call, phone A's BLF for B stays red. A call in the other direction, does not produce the problem. Fanvil ran network captures and says we (you) do not send a Notify to phone A regarding Phone B's call end. My question is, does FS send the Notify regarding B after a call from B ends? If not, I am betting there is a standard somewhere that explains why it is unnecessary - clearly it should not be needed. Thanks for your time, Sean