3G with Asterisk connection

Hello, I'm setting up an Asterisk connection with osmo-sip-connector. Initiation of calls works fine, but no sound is getting through. My setup is as follows: Local computer is running all osmo software plus asterisk interface has IP address 192.168.27.49 plus 192.168.27.47 as alias femtocell is at 192.168.27.41 osmo-mgw.cfg mgcp   bind ip 192.168.27.49   rtp port-range 4002 16000   rtp bind-ip 192.168.27.47 osmo-sip-connector.cfg sip   local 192.168.27.47 5069   remote 192.168.27.49 5060 osmo-msc.cfg msc  mgw remote-ip 192.168.27.49  mgw remote-port 2427  mgw local-port 2728 When I start wireshark it only shows packets flowing between 192.168.27.41(femtocell) and 192.168.27.47(osmo-mgw). No packets to/from Asterisk server, how can I fix this problem? Current documentation on osmo-mgw is quite difficult to understand.