diff --git a/src/machine/usb.go b/src/machine/usb.go
index 7ed4ef35..1449a87b 100644
--- a/src/machine/usb.go
+++ b/src/machine/usb.go
@@ -10,7 +10,8 @@ import (
 )
 
 type USBDevice struct {
-	initcomplete bool
+	initcomplete         bool
+	InitEndpointComplete bool
 }
 
 var (
@@ -215,6 +216,7 @@ func handleStandardSetup(setup usb.Setup) bool {
 			}
 
 			usbConfiguration = setup.WValueL
+			USBDev.InitEndpointComplete = true
 
 			SendZlp()
 			return true
diff --git a/src/machine/usb/hid/keyboard/keyboard.go b/src/machine/usb/hid/keyboard/keyboard.go
index 2dc36e68..ce699399 100644
--- a/src/machine/usb/hid/keyboard/keyboard.go
+++ b/src/machine/usb/hid/keyboard/keyboard.go
@@ -2,6 +2,7 @@ package keyboard
 
 import (
 	"errors"
+	"machine"
 	"machine/usb/hid"
 )
 
@@ -91,11 +92,13 @@ func (kb *keyboard) Handler() bool {
 }
 
 func (kb *keyboard) tx(b []byte) {
-	if kb.waitTxc {
-		kb.buf.Put(b)
-	} else {
-		kb.waitTxc = true
-		hid.SendUSBPacket(b)
+	if machine.USBDev.InitEndpointComplete {
+		if kb.waitTxc {
+			kb.buf.Put(b)
+		} else {
+			kb.waitTxc = true
+			hid.SendUSBPacket(b)
+		}
 	}
 }
 
diff --git a/src/machine/usb/hid/mouse/mouse.go b/src/machine/usb/hid/mouse/mouse.go
index 4d80add4..baf9efb6 100644
--- a/src/machine/usb/hid/mouse/mouse.go
+++ b/src/machine/usb/hid/mouse/mouse.go
@@ -1,6 +1,7 @@
 package mouse
 
 import (
+	"machine"
 	"machine/usb/hid"
 )
 
@@ -55,11 +56,13 @@ func (m *mouse) Handler() bool {
 }
 
 func (m *mouse) tx(b []byte) {
-	if m.waitTxc {
-		m.buf.Put(b)
-	} else {
-		m.waitTxc = true
-		hid.SendUSBPacket(b)
+	if machine.USBDev.InitEndpointComplete {
+		if m.waitTxc {
+			m.buf.Put(b)
+		} else {
+			m.waitTxc = true
+			hid.SendUSBPacket(b)
+		}
 	}
 }
 
diff --git a/src/machine/usb/joystick/joystick.go b/src/machine/usb/joystick/joystick.go
index 9c12997b..d672cbce 100644
--- a/src/machine/usb/joystick/joystick.go
+++ b/src/machine/usb/joystick/joystick.go
@@ -76,11 +76,13 @@ func (m *Joystick) rxHandler(b []byte) {
 }
 
 func (m *Joystick) tx(b []byte) {
-	if m.waitTxc {
-		m.buf.Put(b)
-	} else {
-		m.waitTxc = true
-		m.sendUSBPacket(b)
+	if machine.USBDev.InitEndpointComplete {
+		if m.waitTxc {
+			m.buf.Put(b)
+		} else {
+			m.waitTxc = true
+			m.sendUSBPacket(b)
+		}
 	}
 }
 
diff --git a/src/machine/usb/midi/midi.go b/src/machine/usb/midi/midi.go
index c0796be4..2697866f 100644
--- a/src/machine/usb/midi/midi.go
+++ b/src/machine/usb/midi/midi.go
@@ -71,11 +71,13 @@ func (m *midi) Handler() {
 }
 
 func (m *midi) tx(b []byte) {
-	if m.waitTxc {
-		m.buf.Put(b)
-	} else {
-		m.waitTxc = true
-		m.sendUSBPacket(b)
+	if machine.USBDev.InitEndpointComplete {
+		if m.waitTxc {
+			m.buf.Put(b)
+		} else {
+			m.waitTxc = true
+			m.sendUSBPacket(b)
+		}
 	}
 }