Hello... since quite a while we have the problem that on certain phones you can not hear the caller after picking up a call from a queue. The agent is registered properly, the phone rings - but no audio is transferred. It does not work in both directions. Also logging off and on to the que again does not help. Direct calls to the extension /ddi work just fine without any problems. We checked all settings without any success. One phone is a Snom 370 and the otherone is a Snom D715. 3CX Version is V15 with latest Servicepack. Any ideas how to troubleshoot would be appreciated.