I have about 200 extensions most are Cisco SPA504g and using G711a. I have two sip trunks with two different providers, both using G711a as well. I have disabled "PBX Delivers Audio" on both, one allows Invites the other doesn't seem to as transfers to external numbers fail when enabled. Does this mean the 3CX server will simply pass through the audio from the trunk that supports invites straight to the handset without transcoding? and, will all audio from the trunk that doesn't support Invites be transcoded? Is there a way to tell which calls audio streams are being transcoded and which are being passed on as is.