Hi, I Hope there is help on this forum. I have a 3CX installation with 3 cisco 7940 phones and 1 planet phone. My installation of the cisco 7940 phones is done like the configuration guide from 3cx's discribed. The planet phone has not so much configuration settins en is like a standaard VOIP phone connectet to the 3CX server. The problem is the recieving calls on thes cisco's phone's. When we answerring a call we mostly don't hear the caller. The line seems to be death. The caller can hear us. After a few time switching on the phone between hold en resume sometimes we get the good connections. This is wierd for the caller because he can hear the switching between the music and the person. But most of the times whe have to call the person back. All the rest of the functions work perfectly, whe can call out without a problem. When we recieving calls on the planet Phone all calls are recieved perfectly. After a transfer to a cisco, the problem on the cisco stays. So i am pretty shure that the problem is on the Cisco's. because on a other phone it works fine. Is there a solution for this ?