diff --git a/manager/client.go b/manager/client.go
index b2c0ed3..be9d7ad 100644
--- a/manager/client.go
+++ b/manager/client.go
@@ -23,7 +23,7 @@ func (c *Client) SetEvents(events []string) {
 func NewClient(events []string) Client {
 	return Client{
 		events:      events,
-		payloadChan: make(chan event.Payload),
+		payloadChan: make(chan event.Payload, 20),
 	}
 }
 
diff --git a/server/grpc.go b/server/grpc.go
index 019e322..ce32786 100644
--- a/server/grpc.go
+++ b/server/grpc.go
@@ -85,12 +85,12 @@ type StreamServer struct {
 func NewStreamServer(opt Option) *StreamServer {
 	ss := &StreamServer{
 		clientManager:  manager.NewClientManager(),
-		newClients:     make(chan manager.Client),
-		removeClients:  make(chan manager.Client),
-		payloads:       make(chan event.Payload),
-		errChan:        make(chan error),
-		forceCloseChan: make(chan manager.Client),
-		resfreshEvents: make(chan refreshEvents),
+		newClients:     make(chan manager.Client, 20),
+		removeClients:  make(chan manager.Client, 20),
+		payloads:       make(chan event.Payload, 20),
+		errChan:        make(chan error, 20),
+		forceCloseChan: make(chan manager.Client, 20),
+		resfreshEvents: make(chan refreshEvents, 20),
 		pubsub:         opt.PubSuber,
 		accessLogger:   opt.AccessLogger,
 		errorLogger:    opt.ErrorLogger,