diff --git a/mgw/MGCP_Test.ttcn b/mgw/MGCP_Test.ttcn
index 909ad25..28b7103 100644
--- a/mgw/MGCP_Test.ttcn
+++ b/mgw/MGCP_Test.ttcn
@@ -2351,7 +2351,9 @@
 	/* create two local RTP emulations; create two connections on MGW EP, see if
 	 * exchanged data is converted between AMR octet-aligned and bandwidth
 	 * efficient-mode */
-	function f_TC_amr_x_x_rtp_conversion(octetstring pl0, octetstring pl1, charstring fmtp0, charstring fmtp1) runs on dummy_CT {
+	function f_TC_amr_x_x_rtp_conversion(charstring fmtp0, octetstring pl0,
+					     charstring fmtp1a, octetstring pl1a,
+					     charstring fmtp1b, octetstring pl1b) runs on dummy_CT {
 		var RtpFlowData flow[2];
 		var RtpemStats stats[2];
 		var MgcpResponse resp;
@@ -2372,13 +2374,25 @@
 		f_flow_create(RTPEM[0], ep, call_id, "sendrecv", flow[0]);
 
 		/* Connection #1 (Bidirectional) */
-		flow[1] := valueof(t_RtpFlow(mp_local_ipv4, mp_remote_ipv4, 112, "AMR/8000", fmtp1));
+		flow[1] := valueof(t_RtpFlow(mp_local_ipv4, mp_remote_ipv4, 112, "AMR/8000", fmtp1a));
 		flow[1].em.portnr := 20000;
 		flow[1].rtp_cfg	:= c_RtpemDefaultCfg;
-		flow[1].rtp_cfg.rx_payloads[0].payload_type := flow[1].codec_descr[0].pt;
-		flow[1].rtp_cfg.tx_payloads[0].payload_type := flow[1].codec_descr[0].pt;
-		flow[1].rtp_cfg.rx_payloads[0].fixed_payload := pl1;
-		flow[1].rtp_cfg.tx_payloads[0].fixed_payload := pl1;
+		flow[1].rtp_cfg.rx_payloads := {};
+		flow[1].rtp_cfg.tx_payloads := {};
+		if (pl1a != ''O) {
+			flow[1].rtp_cfg.rx_payloads := flow[1].rtp_cfg.rx_payloads & {{112, pl1a}};
+			flow[1].rtp_cfg.tx_payloads := flow[1].rtp_cfg.tx_payloads & {{112, pl1a}};
+		}
+
+		/* The second fmtp parameter is to simulate a call agent that offers the transmission both modes. */
+		if (fmtp1b != "") {
+			flow[1].codec_descr := flow[1].codec_descr & {{113, "AMR/8000", fmtp1b}};
+			if (pl1b != ''O) {
+				flow[1].rtp_cfg.rx_payloads := flow[1].rtp_cfg.rx_payloads & {{113, pl1b}};
+				flow[1].rtp_cfg.tx_payloads := flow[1].rtp_cfg.tx_payloads & {{113, pl1b}};
+			}
+		}
+
 		f_flow_create(RTPEM[1], ep, call_id, "sendrecv", flow[1]);
 
 		/* Send RTP packets to connection #0, receive on connection #1 */
@@ -2421,16 +2435,41 @@
 	const octetstring rtp_amr_5_15k_oa := '100c4e9ba850e30d5d53d04de41e7c'O;
 	const octetstring rtp_amr_5_15k_bwe := '10d3a6ea1438c35754f41379079f'O;
 
+	/* Only one codec on each side */
 	testcase TC_amr_oa_bwe_rtp_conversion() runs on dummy_CT {
-		f_TC_amr_x_x_rtp_conversion(rtp_amr_5_90k_oa, rtp_amr_5_90k_bwe, "octet-align=1", "octet-align=0");
+		f_TC_amr_x_x_rtp_conversion("octet-align=1", rtp_amr_5_90k_oa, "octet-align=0", rtp_amr_5_90k_bwe, "", ''O);
 	}
-
 	testcase TC_amr_oa_oa_rtp_conversion() runs on dummy_CT {
-		 f_TC_amr_x_x_rtp_conversion(rtp_amr_5_15k_oa, rtp_amr_5_15k_oa, "octet-align=1", "octet-align=1");
+		f_TC_amr_x_x_rtp_conversion("octet-align=1", rtp_amr_5_15k_oa, "octet-align=1", rtp_amr_5_15k_oa, "", ''O);
+	}
+	testcase TC_amr_bwe_bwe_rtp_conversion() runs on dummy_CT {
+		f_TC_amr_x_x_rtp_conversion("octet-align=0", rtp_amr_5_15k_bwe, "octet-align=0", rtp_amr_5_15k_bwe, "", ''O);
 	}
 
-	testcase TC_amr_bwe_bwe_rtp_conversion() runs on dummy_CT {
-		 f_TC_amr_x_x_rtp_conversion(rtp_amr_5_15k_bwe, rtp_amr_5_15k_bwe, "octet-align=0", "octet-align=0");
+	/* Only one codec on one side, two codecs (compatibility) on other side. The payloads are the same on both
+	 * sides, so the expectation is that conversion must not be performed. Each test is done with both formats in
+	 * two different configurations.*/
+	testcase TC_amr_oa_oa_no_bwe_rtp_conversion() runs on dummy_CT {
+		f_TC_amr_x_x_rtp_conversion("octet-align=1", rtp_amr_5_15k_oa,
+					    "octet-align=1", rtp_amr_5_15k_oa,
+					    "octet-align=0", ''O); /* We expect to see NO bandwidth efficient packets! */
+	}
+	testcase TC_amr_oa_no_bwe_oa_rtp_conversion() runs on dummy_CT {
+		/* (Same as above but flipped on the opposite side) */
+		f_TC_amr_x_x_rtp_conversion("octet-align=1", rtp_amr_5_15k_oa,
+					    "octet-align=0", ''O, /* We expect to see NO bandwidth efficient packets! */
+					    "octet-align=1", rtp_amr_5_15k_oa);
+	}
+	testcase TC_amr_bwe_bwe_no_oa_rtp_conversion() runs on dummy_CT {
+		f_TC_amr_x_x_rtp_conversion("octet-align=0", rtp_amr_5_15k_bwe,
+					    "octet-align=0", rtp_amr_5_15k_bwe,
+					    "octet-align=1", ''O); /* We expect to see NO octet aligned packets! */
+	}
+	testcase TC_amr_bwe_no_oa_bwe_rtp_conversion() runs on dummy_CT {
+		/* (Same as above but flipped on the opposite side) */
+		f_TC_amr_x_x_rtp_conversion("octet-align=0", rtp_amr_5_15k_bwe,
+					    "octet-align=1", ''O, /* We expect to see NO octet aligned packets! */
+					    "octet-align=0", rtp_amr_5_15k_bwe);
 	}
 
 	/* TODO: Double-DLCX (no retransmission) */
@@ -3028,6 +3067,10 @@
 		execute(TC_amr_oa_bwe_rtp_conversion());
 		execute(TC_amr_oa_oa_rtp_conversion());
 		execute(TC_amr_bwe_bwe_rtp_conversion());
+		execute(TC_amr_oa_oa_no_bwe_rtp_conversion());
+		execute(TC_amr_oa_no_bwe_oa_rtp_conversion());
+		execute(TC_amr_bwe_bwe_no_oa_rtp_conversion());
+		execute(TC_amr_bwe_no_oa_bwe_rtp_conversion());
 
 		execute(TC_conn_timeout());