diff --git a/udp_mux.go b/udp_mux.go
index f93a546..a477ead 100644
--- a/udp_mux.go
+++ b/udp_mux.go
@@ -365,12 +365,19 @@ func (m *UDPMuxDefault) connWorker() { //nolint:gocognit
 		var destinationConn *udpMuxedConn
 		m.addressMapMu.Lock()
 		if conns, ok := m.addressMap[addr.String()]; ok {
-			destinationConn = conns[ipAddr(localHost.String())]
+			if localHost.IsUnspecified() {
+				for _, c := range conns {
+					destinationConn = c
+					break
+				}
+			} else {
+				destinationConn = conns[ipAddr(localHost.String())]
+			}
 		}
 		m.addressMapMu.Unlock()
 
 		// If we haven't seen this address before but is a STUN packet lookup by ufrag
-		if destinationConn == nil && stun.IsMessage(buf[:n]) {
+		if destinationConn == nil && stun.IsMessage(buf[:n]) && !localHost.IsUnspecified() {
 			msg := &stun.Message{
 				Raw: append([]byte{}, buf[:n]...),
 			}
diff --git a/udpmsghelper.go b/udpmsghelper.go
index b5b95d5..51efa36 100644
--- a/udpmsghelper.go
+++ b/udpmsghelper.go
@@ -1,4 +1,4 @@
-//go:build !js
+//go:build !js && !windows
 
 package ice
 
diff --git a/udpmsghelper_js.go b/udpmsghelper_js_win.go
similarity index 92%
rename from udpmsghelper_js.go
rename to udpmsghelper_js_win.go
index e55911a..51c990a 100644
--- a/udpmsghelper_js.go
+++ b/udpmsghelper_js_win.go
@@ -1,4 +1,4 @@
-//go:build js
+//go:build js || windows
 
 package ice