diff --git a/features/unsupported/USBDevice/USBAudio/USBAudio.cpp b/features/unsupported/USBDevice/USBAudio/USBAudio.cpp
index a0527aaa5d..0d1baff4f3 100644
--- a/features/unsupported/USBDevice/USBAudio/USBAudio.cpp
+++ b/features/unsupported/USBDevice/USBAudio/USBAudio.cpp
@@ -113,6 +113,17 @@ bool USBAudio::write(uint8_t * buf) {
     return true;
 }
 
+void USBAudio::writeSync(uint8_t *buf)
+{
+    USBDevice::writeNB(EP3IN, buf, PACKET_SIZE_ISO_OUT, PACKET_SIZE_ISO_OUT);
+}
+
+uint32_t USBAudio::readSync(uint8_t *buf)
+{
+    uint32_t size = 0;
+    USBDevice::readEP(EP3OUT, (uint8_t *)buf, &size, PACKET_SIZE_ISO_IN);
+    return size;
+}
 
 float USBAudio::getVolume() {
     return (mute) ? 0.0 : volume;
@@ -127,6 +138,10 @@ bool USBAudio::EPISO_OUT_callback() {
         available = true;
         buf_stream_in = NULL;
     }
+    else  {
+        if (rxDone)
+            rxDone.call();
+    }
     readStart(EP3OUT, PACKET_SIZE_ISO_IN);
     return false;
 }
@@ -135,6 +150,8 @@ bool USBAudio::EPISO_OUT_callback() {
 bool USBAudio::EPISO_IN_callback() {
     interruptIN = true;
     writeIN = true;
+    if (txDone) 
+        txDone.call();
     return true;
 }
 
diff --git a/features/unsupported/USBDevice/USBAudio/USBAudio.h b/features/unsupported/USBDevice/USBAudio/USBAudio.h
index f016ff0a0e..b1f9755918 100644
--- a/features/unsupported/USBDevice/USBAudio/USBAudio.h
+++ b/features/unsupported/USBDevice/USBAudio/USBAudio.h
@@ -107,6 +107,14 @@ public:
     */
     bool readNB(uint8_t * buf);
 
+    /**
+     * read last received packet if some.
+     * @param buf pointer on a buffer which will be filled if an audio packet is available
+     *
+     * @returns the packet length
+     */
+    uint32_t readSync(uint8_t *buf);
+
     /**
     * Write an audio packet. During a frame, only a single writing (you can't write and read an audio packet during the same frame)can be done using this method.
     *
@@ -115,6 +123,12 @@ public:
     */
     bool write(uint8_t * buf);
 
+    /**
+     * Write packet in endpoint fifo. assuming tx fifo is empty
+     * @param buf pointer on the audio packet which will be sent
+     */
+    void writeSync(uint8_t *buf);
+
     /**
     * Write and read an audio packet at the same time (on the same frame)
     *
@@ -133,6 +147,22 @@ public:
     void attach(void(*fptr)(void)) {
         updateVol.attach(fptr);
     }
+	/** attach a handler to Tx Done
+     *
+     * @param function Function to attach
+     *
+     */
+    void attachTx(void(*fptr)(void)) {
+        txDone.attach(fptr);
+    }
+    /** attach a handler to Rx Done
+     *
+     * @param function Function to attach
+     *
+     */
+    void attachRx(void(*fptr)(void)) {
+        rxDone.attach(fptr);
+    }
 
     /** Attach a nonstatic void/void member function to update the volume
      *
@@ -144,6 +174,14 @@ public:
     void attach(T *tptr, void(T::*mptr)(void)) {
         updateVol.attach(tptr, mptr);
     }
+	template<typename T>
+	void attachTx(T *tptr, void(T::*mptr)(void)) {
+        txDone.attach(tptr, mptr);
+    }
+    template<typename T>
+	void attachRx(T *tptr, void(T::*mptr)(void)) {
+        rxDone.attach(tptr, mptr);
+    }
 
 
 protected:
@@ -277,6 +315,11 @@ private:
     // callback to update volume
     Callback<void()> updateVol;
 
+    // callback transmit Done
+    Callback<void()> txDone;
+    // callback transmit Done
+    Callback<void()> rxDone;
+
     // boolean showing that the SOF handler has been called. Useful for readNB.
     volatile bool SOF_handler;
 
diff --git a/features/unsupported/tests/usb/device/audio_cb/main.cpp b/features/unsupported/tests/usb/device/audio_cb/main.cpp
new file mode 100644
index 0000000000..ea20170525
--- /dev/null
+++ b/features/unsupported/tests/usb/device/audio_cb/main.cpp
@@ -0,0 +1,51 @@
+// Playback example with the USBAUDIO library
+
+#include "mbed.h"
+#include "USBAudio.h"
+
+// frequency: 48 kHz
+#define FREQ_SPK 16000
+#define FREQ_MIC 16000
+
+// 2channels: stereo
+#define NB_CHA_SPK 2
+#define NB_CHA_MIC 2
+
+// length computed: each ms, we receive 48 * 16bits ->48 * 2 bytes. as there are two channels, the length will be 48 * 2 * 2
+#define LENGTH_AUDIO_PACKET_SPK (FREQ_SPK / 500) * NB_CHA_SPK
+#define LENGTH_AUDIO_PACKET_MIC (FREQ_MIC / 500) * NB_CHA_MIC
+
+// USBAudio object
+USBAudio audio(FREQ_SPK, NB_CHA_SPK, FREQ_MIC, NB_CHA_MIC, 0xab45, 0x0378);
+int filled;
+int ready = 2;
+
+/*  buffer 4 packets to avoid  */
+int buf[4][LENGTH_AUDIO_PACKET_SPK/sizeof(int)];
+void tx_audio(void)
+{
+    /*  used some buffer in advance  */
+    ready = (filled+2)&0x3;
+    audio.writeSync((uint8_t *)buf[ready]);
+}
+
+
+void rx_audio(void)
+{
+    int size=0;
+    int next = (filled + 1)&0x3; 
+    size = audio.readSync((uint8_t *)buf[next]);
+    if (size ) filled = next;
+    if ((size) && (size!=LENGTH_AUDIO_PACKET_MIC)) printf("%d\n",size);
+}
+
+int main()
+{
+    filled = 0;
+    memset(&buf[0][0], 0, sizeof (buf));
+    audio.attachTx(tx_audio);
+    audio.attachRx(rx_audio);
+    /*  start the tx with a silent packet */
+    audio.write((uint8_t *)buf[2]);
+    while(1);
+}
diff --git a/tools/tests.py b/tools/tests.py
index ce49e4fd4c..e24f8d872e 100644
--- a/tools/tests.py
+++ b/tools/tests.py
@@ -1004,6 +1004,11 @@ TESTS = [
         "source_dir": join(TEST_DIR, "usb", "device", "audio"),
         "dependencies": [MBED_LIBRARIES, USB_LIBRARIES],
     },
+    {
+        "id": "USB_8", "description": "AUDIO_CB",
+        "source_dir": join(TEST_DIR, "usb", "device", "audio_cb"),
+        "dependencies": [MBED_LIBRARIES, USB_LIBRARIES],
+    },
 
     # CMSIS DSP
     {