Hi colleagues, after upgrade 3CX from Version 14 to 15.5 and FW Update for snomD765 to recent supported 3CX Version (22.214.171.124) making call doesn´t work in CTI mode. In softphone mode everything is fine. Some informations: We have more than 4 clients and all doesn´t work snomD765 with firmware 126.96.36.199 Windows Client 15.5.7262.2 OS is Windows 7 with 64Bit User Intercom for Make call (Anruf Gegensprechen) is already deactivated (regarding thread from by Jan Koberg, Nov 12, 2017) QoS - hidden tags are already deactivated Reprovision and restarting of snomD765 already performed Also make call from Webclient is working I am looking forward to read from you. Edit: Not supported firmware 188.8.131.52 works fine. I downgraded it and tried it out. Therefore the configuration of actual firmware 184.108.40.206 has something that conflict with it.