diff --git a/README.md b/README.md
index ba349fe..5a79e06 100644
--- a/README.md
+++ b/README.md
@@ -98,16 +98,16 @@ ext_tree = flipper.storage.tree('/ext')
 file_info = flipper.storage.stat("/ext/foo/bar.txt")
 
 #Make directory
-file_info = flipper.storage.mkdir("/ext/foo")
+flipper.storage.mkdir("/ext/foo")
 ```
 #### Files
 
 ```python
 #Read file
-file_info = flipper.storage.read("/ext/foo/bar.txt")
+file= flipper.storage.read("/ext/foo/bar.txt")
 
 #Read file chunks
-file_info = flipper.storage.read("/ext/foo/bar.txt", 42)
+file = flipper.storage.read("/ext/foo/bar.txt", 42)
 
 #Remove file 
 flipper.storage.remove("/ext/foo/bar.txt")
@@ -215,10 +215,20 @@ flipper.gpio.mode(PIN_NAME, 1)
 #Play song in RTTTL format
 rttl_song = "Littleroot Town - Pokemon:d=4,o=5,b=100:8c5,8f5,8g5,4a5,8p,8g5,8a5,8g5,8a5,8a#5,8p,4c6,8d6,8a5,8g5,8a5,8c#6,4d6,4e6,4d6,8a5,8g5,8f5,8e5,8f5,8a5,4d6,8d5,8e5,2f5,8c6,8a#5,8a#5,8a5,2f5,8d6,8a5,8a5,8g5,2f5,8p,8f5,8d5,8f5,8e5,4e5,8f5,8g5"
 
+#Play in loop
 flipper.music_player.play(song)
 
+#Stop loop
+flipper.music_player.stop()
+
+#Play for 20 seconds
+flipper.music_player.play(song, duration=20)
+
 #Beep
 flipper.music_player.beep()
+
+#Beep for 5 seconds
+flipper.music_player.beep(duration=5)
 ```
 ### NFC
 
diff --git a/lib/serial_wrapper.py b/lib/serial_wrapper.py
index 048fb8b..8af2769 100644
--- a/lib/serial_wrapper.py
+++ b/lib/serial_wrapper.py
@@ -16,15 +16,14 @@ class SerialWrapper:
     def __init__(self, port) -> None:
         self._serial_port = serial.Serial(port=port, baudrate=9600,
                                          bytesize=8, timeout=None, stopbits=serial.STOPBITS_ONE)
-        self._serial_port.read_until(b'>')
+        self._serial_port.read_until(b'>:')
 
     @error_handler
-    def send(self, payload):
-        self._serial_port.read()
+    def send(self, payload: str) -> str:
         self._serial_port.write(f"{payload}\r".encode())
         time.sleep(0.5)
         self._serial_port.readline()
-        return self._serial_port.read_until(b'>').decode().rstrip('>\r\n')
+        return self._serial_port.read_until(b'>:').decode().rstrip('\r\n')
     
     def ctrl_c(self):
         self._serial_port.write(b'\x03')
diff --git a/lib/storage.py b/lib/storage.py
index 53e6083..ab99632 100644
--- a/lib/storage.py
+++ b/lib/storage.py
@@ -63,11 +63,17 @@ def remove(self, file):
         return self._serial_wrapper.send(f"storage remove {file}")
 
     def read(self, file):
-        return self._serial_wrapper.send(f"storage read {file}").split('\r\n')[1]
+        try:
+            return self._serial_wrapper.send(f"storage read {file}").split('\r\n')[1]
+        except IndexError:
+            return ""
 
     def read_chunk(self, file, chunks):
-        return self._serial_wrapper.send(f"storage read_chunks {file} {chunks}").split('\r\n')[1]
-
+        try:
+            return self._serial_wrapper.send(f"storage read_chunks {file} {chunks}").split('\r\n')[1]
+        except IndexError:
+            return ""
+            
     def copy(self, source, destination):
         return self._serial_wrapper.send(f"storage copy {source} {destination}")
 
diff --git a/lib/threaded.py b/lib/threaded.py
index 3202a2e..49c50bd 100644
--- a/lib/threaded.py
+++ b/lib/threaded.py
@@ -9,12 +9,11 @@ def __init__(self) -> None:
     def exec(self, func, callback, timeout):
         def _run():
             data = func()
-            if data:
+            if data and callback:
                 callback(func())
         def _timer():
-            if self.thread.is_alive():
-                time.sleep(timeout)
-                self.stop()
+            time.sleep(timeout)
+            self.stop()
         if not self.thread:
             self.thread = Thread(target=_run)
             self.thread.start()