diff --git a/coreapi/bellesip_sal/sal_sdp.c b/coreapi/bellesip_sal/sal_sdp.c
index 0ee29e6da..50e3504a5 100644
--- a/coreapi/bellesip_sal/sal_sdp.c
+++ b/coreapi/bellesip_sal/sal_sdp.c
@@ -117,7 +117,7 @@ static void stream_description_to_sdp ( belle_sdp_session_description_t *session
 			mime_param= belle_sdp_mime_parameter_create ( pt->mime_type
 					, payload_type_get_number ( pt )
 					, pt->clock_rate
-					,stream->type==SalAudio?1:-1 );
+					, pt->channels>0 ? pt->channels : -1 );
 			belle_sdp_mime_parameter_set_parameters ( mime_param,pt->recv_fmtp );
 			if ( stream->ptime>0 ) {
 				belle_sdp_mime_parameter_set_ptime ( mime_param,stream->ptime );
diff --git a/coreapi/linphonecore.c b/coreapi/linphonecore.c
index c31d1c181..b15bd71b4 100644
--- a/coreapi/linphonecore.c
+++ b/coreapi/linphonecore.c
@@ -1377,7 +1377,7 @@ static void linphone_core_init(LinphoneCore * lc, const LinphoneCoreVTable *vtab
 	linphone_core_assign_payload_type(lc,&payload_type_g729,18,"annexb=no");
 	linphone_core_assign_payload_type(lc,&payload_type_aaceld_22k,-1,"config=F8EE2000; constantDuration=512;  indexDeltaLength=3; indexLength=3; mode=AAC-hbr; profile-level-id=76; sizeLength=13; streamType=5");
 	linphone_core_assign_payload_type(lc,&payload_type_aaceld_44k,-1,"config=F8E82000; constantDuration=512;  indexDeltaLength=3; indexLength=3; mode=AAC-hbr; profile-level-id=76; sizeLength=13; streamType=5");
-	linphone_core_assign_payload_type(lc,&payload_type_opus,-1,"useinbandfec=1; usedtx=0; cbr=1");
+	linphone_core_assign_payload_type(lc,&payload_type_opus,-1,"useinbandfec=1; stereo=0; sprop-stereo=0");
 	linphone_core_assign_payload_type(lc,&payload_type_isac,-1,NULL);
 	linphone_core_handle_static_payloads(lc);
 
diff --git a/coreapi/misc.c b/coreapi/misc.c
index b1e9f2235..fed8191b4 100644
--- a/coreapi/misc.c
+++ b/coreapi/misc.c
@@ -168,12 +168,6 @@ bool_t linphone_core_is_payload_type_usable_for_bandwidth(LinphoneCore *lc, Payl
 		case PAYLOAD_AUDIO_PACKETIZED:
 			codec_band=get_audio_payload_bandwidth(lc,pt);
 			ret=bandwidth_is_greater(bandwidth_limit*1000,codec_band);
-			/*hack to avoid using uwb codecs when having low bitrate and video*/
-			if (bandwidth_is_greater(199,bandwidth_limit)){
-				if (linphone_core_video_enabled(lc) && pt->clock_rate>16000){
-					ret=FALSE;
-				}
-			}
 			//ms_message("Payload %s: %g",pt->mime_type,codec_band);
 			break;
 		case PAYLOAD_VIDEO:
diff --git a/coreapi/offeranswer.c b/coreapi/offeranswer.c
index df4e7507d..db2a28b76 100644
--- a/coreapi/offeranswer.c
+++ b/coreapi/offeranswer.c
@@ -39,11 +39,20 @@ static PayloadType * find_payload_type_best_match(const MSList *l, const Payload
 
 	for (elem=l;elem!=NULL;elem=elem->next){
 		pt=(PayloadType*)elem->data;
+		
+		/*workaround a bug in earlier versions of linphone where opus/48000/1 is offered, which is uncompliant with opus rtp draft*/
+		if (refpt->mime_type && strcasecmp(refpt->mime_type,"opus")==0 && refpt->channels==1
+			&& strcasecmp(pt->mime_type,refpt->mime_type)==0){
+			pt->channels=1; /*so that we respond with same number of channels */
+			candidate=pt;
+			break;
+		}
+		
 		/* the compare between G729 and G729A is for some stupid uncompliant phone*/
 		if ( pt->mime_type && refpt->mime_type &&
 			(strcasecmp(pt->mime_type,refpt->mime_type)==0  ||
 			(strcasecmp(pt->mime_type, "G729") == 0 && strcasecmp(refpt->mime_type, "G729A") == 0 ))
-			&& pt->clock_rate==refpt->clock_rate){
+			&& pt->clock_rate==refpt->clock_rate && pt->channels==refpt->channels){
 			candidate=pt;
 			/*good candidate, check fmtp for H264 */
 			if (strcasecmp(pt->mime_type,"H264")==0){
@@ -106,7 +115,9 @@ static MSList *match_payloads(const MSList *local, const MSList *remote, bool_t
 				res=ms_list_append(res,newp);
 			}
 		}else{
-			ms_message("No match for %s/%i",p2->mime_type,p2->clock_rate);
+			if (p2->channels>0)
+				ms_message("No match for %s/%i/%i",p2->mime_type,p2->clock_rate,p2->channels);
+			else ms_message("No match for %s/%i",p2->mime_type,p2->clock_rate);
 		}
 	}
 	if (reading_response){
diff --git a/mediastreamer2 b/mediastreamer2
index f6c6813f0..7f97a5c70 160000
--- a/mediastreamer2
+++ b/mediastreamer2
@@ -1 +1 @@
-Subproject commit f6c6813f0cdffaaa290d3933b7f6a92d586bae72
+Subproject commit 7f97a5c7046589f4de0a742a686308ad5770348d
diff --git a/oRTP b/oRTP
index c09e63ddb..c329c3a47 160000
--- a/oRTP
+++ b/oRTP
@@ -1 +1 @@
-Subproject commit c09e63ddba599a7f7da149edf6f7b290f4cfa787
+Subproject commit c329c3a478011ed4c10ffca79b8624ec6b60450c