diff --git a/internal/broadcasts/attendants.go b/internal/broadcasts/attendants.go
index 0ad1fd9..d6bdb3c 100644
--- a/internal/broadcasts/attendants.go
+++ b/internal/broadcasts/attendants.go
@@ -52,7 +52,6 @@ func (bcst *AttendantsBroadcast) Register(sink AttendantsEmitter) func() {
 type attendantsSink AttendantsBroadcast
 
 func (bcst *attendantsSink) Joined(member refs.FeedRef) error {
-
 	bcst.mu.Lock()
 	for s := range bcst.sinks {
 		err := (*s).Joined(member)
@@ -66,7 +65,6 @@ func (bcst *attendantsSink) Joined(member refs.FeedRef) error {
 }
 
 func (bcst *attendantsSink) Left(member refs.FeedRef) error {
-
 	bcst.mu.Lock()
 	for s := range bcst.sinks {
 		err := (*s).Left(member)
@@ -81,7 +79,13 @@ func (bcst *attendantsSink) Left(member refs.FeedRef) error {
 
 // Close implements the Sink interface.
 func (bcst *attendantsSink) Close() error {
-	var sinks []AttendantsEmitter
+	bcst.mu.Lock()
+	defer bcst.mu.Unlock()
+	sinks := make([]AttendantsEmitter, 0, len(bcst.sinks))
+
+	for sink := range bcst.sinks {
+		sinks = append(sinks, *sink)
+	}
 
 	bcst.mu.Lock()
 	defer bcst.mu.Unlock()
diff --git a/muxrpc/test/go/attendants_test.go b/muxrpc/test/go/attendants_test.go
index 9e4e2ff..ace0e09 100644
--- a/muxrpc/test/go/attendants_test.go
+++ b/muxrpc/test/go/attendants_test.go
@@ -50,7 +50,7 @@ func TestRoomAttendants(t *testing.T) {
 
 	carlsSource, err := carl.Source(ctx, muxrpc.TypeJSON, muxrpc.Method{"room", "attendants"})
 	r.NoError(err)
-	t.Log("sarah opened endpoints")
+	t.Log("carl opened attendants")
 
 	// first message should be initial state
 	a.True(carlsSource.Next(ctx))