diff --git a/coreapi/linphonecore.c b/coreapi/linphonecore.c
index 452447232..0befb3cd4 100644
--- a/coreapi/linphonecore.c
+++ b/coreapi/linphonecore.c
@@ -5930,7 +5930,7 @@ static void linphone_core_uninit(LinphoneCore *lc)
 		linphone_presence_model_unref(lc->presence_model);
 	}
 	linphone_core_free_payload_types(lc);
-
+	if (lc->supported_formats) ms_free(lc->supported_formats);
 	linphone_core_message_storage_close(lc);
 	ms_exit();
 	linphone_core_set_state(lc,LinphoneGlobalOff,"Off");
diff --git a/coreapi/linphonecore.h b/coreapi/linphonecore.h
index dd0ff311a..89fd4723a 100644
--- a/coreapi/linphonecore.h
+++ b/coreapi/linphonecore.h
@@ -2602,6 +2602,14 @@ LINPHONE_PUBLIC void linphone_core_set_tone(LinphoneCore *lc, LinphoneToneID id,
  * */
 LINPHONE_PUBLIC void linphone_core_set_file_transfer_server(LinphoneCore *core, const char * server_url);
 
+/**
+ * Returns a null terminated table of strings containing the file format extension supported for call recording.
+ * @param core the core
+ * @return the supported formats, typically 'wav' and 'mkv'
+ * @ingroup media_parameters
+**/
+LINPHONE_PUBLIC const char ** linphone_core_get_supported_file_formats(LinphoneCore *core);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/coreapi/misc.c b/coreapi/misc.c
index 43b3a3139..a058db102 100644
--- a/coreapi/misc.c
+++ b/coreapi/misc.c
@@ -1522,3 +1522,18 @@ const MSCryptoSuite * linphone_core_get_srtp_crypto_suites(LinphoneCore *lc){
 	lc->rtp_conf.srtp_suites=result;
 	return result;
 }
+
+
+
+const char ** linphone_core_get_supported_file_formats(LinphoneCore *core){
+	static const char *mkv="mkv";
+	static const char *wav="wav";
+	if (core->supported_formats==NULL){
+		core->supported_formats=ms_malloc0(3*sizeof(char*));
+		core->supported_formats[0]=wav;
+		if (ms_factory_lookup_filter_by_id(ms_factory_get_fallback(),MS_MKV_WRITER_ID)){
+			core->supported_formats[1]=mkv;
+		}
+	}
+	return core->supported_formats;
+}
diff --git a/coreapi/private.h b/coreapi/private.h
index b59ccd906..49e3fb72e 100644
--- a/coreapi/private.h
+++ b/coreapi/private.h
@@ -726,6 +726,7 @@ struct _LinphoneCore
 	MSList *tones;
 	LinphoneReason chat_deny_code;
 	char *file_transfer_server;
+	const char **supported_formats;
 };
 
 
diff --git a/gtk/main.c b/gtk/main.c
index c1a52cda4..c987b4f9e 100644
--- a/gtk/main.c
+++ b/gtk/main.c
@@ -983,6 +983,9 @@ gchar *linphone_gtk_get_record_path(const LinphoneAddress *address, gboolean is_
 	char date[64]={0};
 	time_t curtime=time(NULL);
 	struct tm loctime;
+	const char **fmts=linphone_core_get_supported_file_formats(linphone_gtk_get_core());
+	int i;
+	const char *ext="wav";
 	
 #ifdef WIN32
 	loctime=*localtime(&curtime);
@@ -991,19 +994,26 @@ gchar *linphone_gtk_get_record_path(const LinphoneAddress *address, gboolean is_
 #endif
 	snprintf(date,sizeof(date)-1,"%i%02i%02i-%02i%02i",loctime.tm_year+1900,loctime.tm_mon+1,loctime.tm_mday, loctime.tm_hour, loctime.tm_min);
 	
+	for (i=0;fmts[i]!=NULL;++i){
+		if (strcmp(fmts[i],"mkv")==0){
+			ext="mkv";
+			break;
+		}
+	}
+	
 	if (address){
 		id=linphone_address_get_username(address);
 		if (id==NULL) id=linphone_address_get_domain(address);
 	}
 	if (is_conference){
-		snprintf(filename,sizeof(filename)-1,"%s-conference-%s.wav",
+		snprintf(filename,sizeof(filename)-1,"%s-conference-%s.%s",
 			linphone_gtk_get_ui_config("title","Linphone"),
-			date);
+			date,ext);
 	}else{
-		snprintf(filename,sizeof(filename)-1,"%s-call-%s-%s.wav",
+		snprintf(filename,sizeof(filename)-1,"%s-call-%s-%s.%s",
 			linphone_gtk_get_ui_config("title","Linphone"),
 			date,
-			id);
+			id,ext);
 	}
 	if (!dir) {
 		ms_message ("No directory for music, using [%s] instead",dir=getenv("HOME"));
diff --git a/mediastreamer2 b/mediastreamer2
index df42f0d73..a7846bc24 160000
--- a/mediastreamer2
+++ b/mediastreamer2
@@ -1 +1 @@
-Subproject commit df42f0d73d930079c43ef92808529a4716e72d99
+Subproject commit a7846bc24f3e5bb1cc89faf879f6d64638665585