diff --git a/asterisk/SIP_ConnectionHandler.ttcn b/asterisk/SIP_ConnectionHandler.ttcn
index 41a29e4..a14dd03 100644
--- a/asterisk/SIP_ConnectionHandler.ttcn
+++ b/asterisk/SIP_ConnectionHandler.ttcn
@@ -241,7 +241,8 @@
 		"t=0 0\r\n" &
 		"a=rtcp-xr:rcvr-rtt=all:10000 stat-summary=loss,dup,jitt,TTL voip-metrics\r\n" &
 		"a=record:off\r\n" &
-		"m=audio " & int2str(g_pars.cp.local_rtp_port) & " RTP/AVP 96 97 98 0 8 18 99 100 101\r\n" &
+		"m=audio " & int2str(g_pars.cp.local_rtp_port) & " RTP/AVP 8 96 97 98 0 18 99 100 101\r\n" &
+		"a=rtpmap:8 PCMA/8000\r\n" &
 		"a=rtpmap:96 opus/48000/2\r\n" &
 		"a=fmtp:96 useinbandfec=1\r\n" &
 		"a=rtpmap:97 speex/16000\r\n" &