diff --git a/client.go b/client.go
index faff8c3..9b5713e 100644
--- a/client.go
+++ b/client.go
@@ -346,9 +346,28 @@ func addUpConn(c *client, id string) (*upConnection, error) {
 			c.mu.Unlock()
 			return
 		}
+
+		mid := getUpMid(pc, remote)
+		if mid == "" {
+			log.Printf("Couldn't get track's mid")
+			c.mu.Unlock()
+			return
+		}
+
+		label, ok := u.labels[mid]
+		if !ok {
+			log.Printf("Couldn't get track's label")
+			isvideo := remote.Kind() == webrtc.RTPCodecTypeVideo
+			if isvideo {
+				label = "video"
+			} else {
+				label = "audio"
+			}
+		}
+
 		track := &upTrack{
 			track:      remote,
-			label:      u.labels[remote.ID()],
+			label:      label,
 			cache:      packetcache.New(96),
 			rate:       estimator.New(time.Second),
 			jitter:     jitter.New(remote.Codec().ClockRate),
@@ -957,8 +976,20 @@ func negotiate(c *client, down *downConnection) error {
 	}
 
 	labels := make(map[string]string)
-	for _, t := range down.tracks {
-		labels[t.track.ID()] = t.remote.label
+	for _, t := range down.pc.GetTransceivers() {
+		var track *webrtc.Track
+		if t.Sender() != nil {
+			track = t.Sender().Track()
+		}
+		if track == nil {
+			continue
+		}
+
+		for _, tr := range down.tracks {
+			if tr.track == track {
+				labels[t.Mid()] = tr.remote.label
+			}
+		}
 	}
 
 	return c.write(clientMessage{
diff --git a/group.go b/group.go
index 421f411..1827944 100644
--- a/group.go
+++ b/group.go
@@ -96,11 +96,21 @@ type upConnection struct {
 	labels map[string]string
 }
 
+func getUpMid(pc *webrtc.PeerConnection, track *webrtc.Track) string {
+	for _, t := range pc.GetTransceivers() {
+		if t.Receiver() != nil && t.Receiver().Track() == track {
+			return t.Mid()
+		}
+	}
+	return ""
+}
+
 func (up *upConnection) complete() bool {
-	for id, _ := range up.labels {
+	for mid, _ := range up.labels {
 		found := false
 		for _, t := range up.tracks {
-			if t.track.ID() == id {
+			m := getUpMid(up.pc, t.track)
+			if m == mid {
 				found = true
 				break
 			}
diff --git a/static/sfu.js b/static/sfu.js
index f89f6cd..e801c1f 100644
--- a/static/sfu.js
+++ b/static/sfu.js
@@ -41,6 +41,7 @@ function Connection(id, pc) {
     this.pc = pc;
     this.stream = null;
     this.labels = {};
+    this.labelsByMid = {};
     this.iceCandidates = [];
     this.timers = [];
     this.audioStats = {};
@@ -647,12 +648,18 @@ async function gotOffer(id, labels, offer) {
         };
 
         c.pc.ontrack = function(e) {
+            let label = e.transceiver && c.labelsByMid[e.transceiver.mid];
+            if(label) {
+                c.labels[e.track.id] = label;
+            } else {
+                console.error("Couldn't find label for track");
+            }
             c.stream = e.streams[0];
             setMedia(id);
         };
     }
 
-    c.labels = labels;
+    c.labelsByMid = labels;
 
     await c.pc.setRemoteDescription(offer);
     await addIceCandidates(c);
@@ -1066,10 +1073,22 @@ async function negotiate(id) {
     if(!offer)
         throw(new Error("Didn't create offer"));
     await c.pc.setLocalDescription(offer);
+
+    // mids are not known until this point
+    c.pc.getTransceivers().forEach(t => {
+        if(t.sender && t.sender.track) {
+            let label = c.labels[t.sender.track.id];
+            if(label)
+                c.labelsByMid[t.mid] = label;
+            else
+                console.error("Couldn't find label for track");
+        }
+    });
+
     send({
         type: 'offer',
         id: id,
-        labels: c.labels,
+        labels: c.labelsByMid,
         offer: offer,
     });
 }