I am having difficulties forcefully stripping the a:crypto lines from the remote sdp string. At first i was doing <action application="set"><![CDATA[switch_r_sdp=$sdp]]> </action> from the diaplan, but this breaks the proxy media easily, because it doesn't patch the SDP later for glueing. I commented the following lines where the patcher is checking if the sdp string has been set before : void sofia_glue_tech_patch_sdp(private_object_t *tech_pvt) { switch_size_t len; char *p, *q, *pe, *qe; int has_video = 0, has_audio = 0, has_ip = 0; char port_buf[25] = ""; char vport_buf[25] = ""; char *new_sdp; int bad = 0; */** * if (zstr(tech_pvt->local_sdp_str)) {* * return;* * }* **/* And now i got the correct sdp sent to the b-leg(patched for proxy media and nat), but no audio is going either way. Would there be a more clever way to "rip" some lines from the SDP and not break the NAT/Proxy media processing afterwards? Help is much appreciated.