Hi guys, I've investigated many hours and cannot solve this problem: A and B should use g711u. A: B: But FreeSwitch decides to transcode: The settings: vars.xml <X-PRE-PROCESS cmd="set" data="media_mix_inbound_outbound_codecs=false"/> <X-PRE-PROCESS cmd="set" data="global_codec_prefs=OPUS,G722,PCMU,PCMA,VP8"/> internal.xml <param name="inbound-codec-negotiation" value="greedy"/> <param name="inbound-late-negotiation" value="true"/> <param name="disable-transcoding" value="true"/> <param name="inbound-proxy-media" value="false"/> <param name="inbound-bypass-media" value="false"/> <param name="inbound-codec-prefs" value="$${global_codec_prefs}"/> <param name="outbound-codec-prefs" value="$${global_codec_prefs}"/> default.xml (Using the demo-Dialplan) <extension name="Local_Extension"> ... Using FS v 1.8 Thanks. Uli
