diff --git a/app.py b/app.py
index 34ebc0c..f8946a1 100644
--- a/app.py
+++ b/app.py
@@ -56,6 +56,7 @@ def xml_transfer():
                     str(dir + '/XML/config.xml'))
                 xml_reader.set_root(str(dir + '/XML/config.xml'))
                 interface_handler.init_gpio()
+                interface_handler.init_buffer()
             else:
                 SyntaxError('the config.xml has invalid content')
             return {'error': ''}
diff --git a/interface_handler.py b/interface_handler.py
index e51c1e5..132deb5 100644
--- a/interface_handler.py
+++ b/interface_handler.py
@@ -60,6 +60,7 @@ class Interface_handler:
         self.buffers = [None] * 41
         self.buffer_device_names = []
         self.buffer_thread = None
+        self.run_buffer = False
         self.init_gpio()
         self.init_buffer()
 
@@ -97,8 +98,10 @@ class Interface_handler:
         """initializes the buffer thread 
         """
         #stop the buffer thread 
-        if self.buffer_thread != None:
-            self.buffer_thread.stop()
+        self.run_buffer = False
+        while self.buffer_thread!=None and self.buffer_thread.is_alive():
+            time.sleep(BUFFER_SPEED)
+        self.run_buffer = True
         #create the buffers
         for device_name in self.xml_reader.get_device_names():
             port_info = self.xml_reader.get_port(device_name)
@@ -241,7 +244,7 @@ class Interface_handler:
     def buffering(self):
         """method that buffers the device outputs
         """
-        while True: #loop forever
+        while self.run_buffer: #loop
             for device_name in self.buffer_device_names:
                 output = self.read(device_name)
                 port_info = self.xml_reader.get_port(device_name)