diff --git a/device.go b/device.go
index f9f6707..359edea 100644
--- a/device.go
+++ b/device.go
@@ -184,14 +184,11 @@ func (nc *NetCard) runRead() {
 		for atomic.LoadInt32(&isLoop) > 0 {
 			var rframe ethernet.Frame
 			rframe.Resize(1500)
-
-			nc.Lock(func() {
-				n, err := ifce.Read([]byte(rframe))
-				if err != nil {
-					log.Fatal(err)
-				}
-				rframe = rframe[:n]
-			})
+			n, err := ifce.Read([]byte(rframe))
+			if err != nil {
+				log.Fatal(err)
+			}
+			rframe = rframe[:n]
 
 			if !waterutil.IsIPv4(rframe) || waterutil.IPv4Source(rframe).Equal(net.IPv4(0, 0, 0, 0)) {
 				continue
@@ -204,6 +201,7 @@ func (nc *NetCard) runRead() {
 				}
 			})
 			if realAddr == "" {
+				log.Printf("%s is not exists", waterutil.IPv4Destination(rframe))
 				continue
 			}
 
@@ -272,14 +270,12 @@ func (nc *NetCard) runWrite() {
 
 		log.Printf("get wframes decode len: %d", len(bufs[0]))
 
-		nc.Lock(func() {
-			for _, buf := range bufs {
-				_, err := ifce.Write(buf)
-				if err != nil {
-					log.Panic(err)
-				}
+		for _, buf := range bufs {
+			_, err := ifce.Write(buf)
+			if err != nil {
+				log.Panic(err)
 			}
-		})
+		}
 
 	}