I'm configured freeswitch with gsmopen but can't seem to figure where why I only get voice out from SIP-client to mobile-phone but not voice from mobile to SIP client. When I tried to call from mobile-phone to IVR extension 5000 and press 2 for the standard echo test (9196), I could hear the echo back. When I tried to call 9195 for the five second delay echo test, I couldn't anything. I've add these settings in vars.xml as well. <X-PRE-PROCESS cmd="set" data="media_mix_inbound_outbound_codecs=true"/> <X-PRE-PROCESS cmd="set" data="inbound-late-negotiation=false"/> <X-PRE-PROCESS cmd="set" data="inbound-zrtp-passthru=false"/> <X-PRE-PROCESS cmd="set" data="disable-transcoding=false"/> <X-PRE-PROCESS cmd="set" data="inherit_codec=false"/> <X-PRE-PROCESS cmd="set" data="bypass_media=false"/> <X-PRE-PROCESS cmd="set" data="proxy_media=false"/> What am I missing? Thanks, Jeff