--- a/libavformat/rtsp.c
+++ b/libavformat/rtsp.c
@@ -2380,6 +2380,8 @@ static int sdp_read_header(AVFormatContext *s)
     int size, i, err;
     char *content;
     char url[MAX_URL_SIZE];
+    const char *p, *sp="", *sources="", *sp2, *sources2;
+    char sources_buf[1024];
 
     if (!ff_network_init())
         return AVERROR(EIO);
@@ -2408,6 +2410,16 @@ static int sdp_read_header(AVFormatContext *s)
     av_freep(&content);
     if (err) goto fail;
 
+    /* Search for sources= tag in original URL for rtp protocol only */
+    if (strncmp(s->url, "rtp://", 6) == 0) {
+        p = strchr(s->url, '?');
+        if (p && av_find_info_tag(sources_buf, sizeof(sources_buf), "sources", p)) {
+            /* av_log(s, AV_LOG_VERBOSE, "sdp_read_header found sources %s\n", sources_buf);  */
+            sp = sources_buf;
+            sources = "&sources=";
+        }
+    }
+
     /* open each RTP stream */
     for (i = 0; i < rt->nb_rtsp_streams; i++) {
         char namebuf[50];
@@ -2425,12 +2437,22 @@ static int sdp_read_header(AVFormatContext *s)
                 av_dict_free(&opts);
                 goto fail;
             }
+
+            /* Prepare to add sources to the url to be opened.
+               Otherwise the join to the source specific muliticast will be missing */
+            sources2 = sources;
+            sp2 = sp;
+            /* ignore sources from original URL, when sources are already set in rtsp_st */
+            if (rtsp_st->nb_include_source_addrs > 0)
+                sources2 = sp2 = "";
+
             ff_url_join(url, sizeof(url), "rtp", NULL,
                         namebuf, rtsp_st->sdp_port,
-                        "?localport=%d&ttl=%d&connect=%d&write_to_source=%d",
+                        "?localport=%d&ttl=%d&connect=%d&write_to_source=%d%s%s",
                         rtsp_st->sdp_port, rtsp_st->sdp_ttl,
                         rt->rtsp_flags & RTSP_FLAG_FILTER_SRC ? 1 : 0,
-                        rt->rtsp_flags & RTSP_FLAG_RTCP_TO_SOURCE ? 1 : 0);
+                        rt->rtsp_flags & RTSP_FLAG_RTCP_TO_SOURCE ? 1 : 0,
+                        sources2, sp2);
 
             append_source_addrs(url, sizeof(url), "sources",
                                 rtsp_st->nb_include_source_addrs,