diff --git a/pkg/router.go b/pkg/router.go
index 178fbd954..654cba975 100644
--- a/pkg/router.go
+++ b/pkg/router.go
@@ -202,6 +202,15 @@ func (r *router) addSender(p *WebRTCTransport, rr *receiverRouter) error {
 			log.Errorf("Error closing sender: %s", err)
 		}
 	})
+	for _, t := range p.pc.GetTransceivers() {
+		if t.Sender() != nil && t.Sender().Track().SSRC() == ssrc {
+			p.pendingSenders.PushBack(&pendingSender{
+				transceiver: t,
+				sender:      sender,
+			})
+			break
+		}
+	}
 	p.AddSender(rr.stream, sender)
 	recv.AddSender(sender)
 	return nil
diff --git a/pkg/webrtctransport.go b/pkg/webrtctransport.go
index 1ed2d5e69..5d055444f 100644
--- a/pkg/webrtctransport.go
+++ b/pkg/webrtctransport.go
@@ -7,6 +7,8 @@ import (
 	"sync"
 	"time"
 
+	"github.com/gammazero/deque"
+
 	"github.com/bep/debounce"
 	"github.com/lucsky/cuid"
 	log "github.com/pion/ion-log"
@@ -24,21 +26,26 @@ type WebRTCTransportConfig struct {
 // WebRTCTransport represents a sfu peer connection
 type WebRTCTransport struct {
 	id             string
-	ctx            context.Context
-	cancel         context.CancelFunc
 	pc             *webrtc.PeerConnection
 	me             MediaEngine
 	mu             sync.RWMutex
-	candidates     []webrtc.ICECandidateInit
+	ctx            context.Context
+	cancel         context.CancelFunc
+	router         Router
 	session        *Session
-	mids           map[string]Sender
 	senders        map[string][]Sender
-	router         Router
+	candidates     []webrtc.ICECandidateInit
+	pendingSenders deque.Deque
 	onTrackHandler func(*webrtc.Track, *webrtc.RTPReceiver)
 
 	subOnce sync.Once
 }
 
+type pendingSender struct {
+	transceiver *webrtc.RTPTransceiver
+	sender      Sender
+}
+
 // NewWebRTCTransport creates a new WebRTCTransport
 func NewWebRTCTransport(ctx context.Context, session *Session, me MediaEngine, cfg WebRTCTransportConfig) (*WebRTCTransport, error) {
 	api := webrtc.NewAPI(webrtc.WithMediaEngine(me.MediaEngine), webrtc.WithSettingEngine(cfg.setting))
@@ -59,9 +66,9 @@ func NewWebRTCTransport(ctx context.Context, session *Session, me MediaEngine, c
 		me:      me,
 		session: session,
 		router:  newRouter(pc, id, cfg.router),
-		mids:    make(map[string]Sender),
 		senders: make(map[string][]Sender),
 	}
+	p.pendingSenders.SetMinCapacity(2)
 
 	// Add transport to the session
 	session.AddTransport(p)
@@ -124,58 +131,12 @@ func NewWebRTCTransport(ctx context.Context, session *Session, me MediaEngine, c
 
 // CreateOffer generates the localDescription
 func (p *WebRTCTransport) CreateOffer() (webrtc.SessionDescription, error) {
-	offer, err := p.pc.CreateOffer(nil)
-	if err != nil {
-		return webrtc.SessionDescription{}, err
-	}
-	parsed := sdp.SessionDescription{}
-	if err := parsed.Unmarshal([]byte(offer.SDP)); err == nil {
-		for _, md := range parsed.MediaDescriptions {
-			if md.MediaName.Media != mediaNameAudio && md.MediaName.Media != mediaNameVideo {
-				continue
-			}
-			var msid, mid string
-
-			for _, att := range md.Attributes {
-				switch att.Key {
-				case sdp.AttrKeyMID:
-					mid = att.Value
-					if len(msid) > 0 {
-						break
-					}
-				case sdp.AttrKeyMsid:
-					msid = att.Value
-					if len(mid) > 0 {
-						break
-					}
-				}
-			}
-			if len(msid) > 0 && len(mid) > 0 {
-				split := strings.Split(msid, " ")
-				sid := split[0]
-				tid := split[1]
-				// find sender for mid
-				for _, sender := range p.senders[sid] {
-					if sender.Track().ID() == tid {
-						p.mids[mid] = sender
-					}
-				}
-			}
-		}
-	}
-
-	return offer, nil
+	return p.pc.CreateOffer(nil)
 }
 
 // SetLocalDescription sets the SessionDescription of the remote peer
 func (p *WebRTCTransport) SetLocalDescription(desc webrtc.SessionDescription) error {
-	err := p.pc.SetLocalDescription(desc)
-	if err != nil {
-		log.Errorf("SetLocalDescription error: %v", err)
-		return err
-	}
-
-	return nil
+	return p.pc.SetLocalDescription(desc)
 }
 
 // CreateAnswer generates the localDescription
@@ -212,42 +173,50 @@ func (p *WebRTCTransport) SetRemoteDescription(desc webrtc.SessionDescription) e
 		p.candidates = nil
 	}
 
-	for _, md := range pd.MediaDescriptions {
-		if md.MediaName.Media != mediaNameAudio && md.MediaName.Media != mediaNameVideo {
-			continue
-		}
-		var (
-			ext int
-			id  string
-		)
-
-		for _, att := range md.Attributes {
-			if att.Key == sdp.AttrKeyMID {
-				if p.mids[att.Value] != nil {
-					p.mids[att.Value].Start()
-					// remove mid mapping in case transceiver is reused later
-					p.mids[att.Value] = nil
+	switch desc.Type {
+	case webrtc.SDPTypeAnswer:
+		if p.pendingSenders.Len() != 0 {
+			for _, md := range pd.MediaDescriptions {
+				if mid, ok := md.Attribute(sdp.AttrKeyMID); ok {
+					for i := 0; i < p.pendingSenders.Len(); i++ {
+						ps := p.pendingSenders.PopFront().(*pendingSender)
+						if ps.transceiver.Mid() == mid {
+							ps.sender.Start()
+						} else {
+							p.pendingSenders.PushBack(ps)
+						}
+					}
 				}
 			}
-
-			if att.Key == sdp.AttrKeyExtMap && strings.HasSuffix(att.Value, sdp.TransportCCURI) {
-				ext, _ = strconv.Atoi(att.Value[:1])
-				if len(id) > 0 {
-					break
-				}
+		}
+	case webrtc.SDPTypeOffer:
+		for _, md := range pd.MediaDescriptions {
+			if md.MediaName.Media != mediaNameAudio && md.MediaName.Media != mediaNameVideo {
+				continue
 			}
-			if att.Key == sdp.AttrKeyMsid {
-				v := strings.Split(att.Value, " ")
-				id = v[len(v)-1]
-				if ext != 0 {
-					break
+			var (
+				ext int
+				id  string
+			)
+			for _, att := range md.Attributes {
+				if att.Key == sdp.AttrKeyExtMap && strings.HasSuffix(att.Value, sdp.TransportCCURI) {
+					ext, _ = strconv.Atoi(att.Value[:1])
+					if len(id) > 0 {
+						break
+					}
+				}
+				if att.Key == sdp.AttrKeyMsid {
+					v := strings.Split(att.Value, " ")
+					id = v[len(v)-1]
+					if ext != 0 {
+						break
+					}
 				}
 			}
-		}
-		p.router.AddTWCCExt(id, ext)
+			p.router.AddTWCCExt(id, ext)
 
+		}
 	}
-
 	return nil
 }