diff --git a/lasp/device/lasp_daqconfig.py b/lasp/device/lasp_daqconfig.py
index ca8ba20..9bf812e 100644
--- a/lasp/device/lasp_daqconfig.py
+++ b/lasp/device/lasp_daqconfig.py
@@ -164,8 +164,10 @@ class DAQConfiguration:
         return [ch.qty for ch in self.getEnabledInputChannels()]
 
     def getEnabledInputChannelSensitivities(self):
-        return [float(channel.sensitivity) for channel in
-                    self.getEnabledInputChannels()]
+        return [
+            float(channel.sensitivity)
+            for channel in self.getEnabledInputChannels()
+        ]
 
     def getEnabledOutputChannels(self):
         en_channels = []
@@ -178,8 +180,10 @@ class DAQConfiguration:
         return [ch.qty for ch in self.getEnabledOutputChannels()]
 
     def getEnabledOutputChannelSensitivities(self):
-        return [float(channel.sensitivity) for channel in
-                    self.getEnabledOutputChannels()]
+        return [
+            float(channel.sensitivity)
+            for channel in self.getEnabledOutputChannels()
+        ]
 
     @staticmethod
     def loadConfigsJSON():
@@ -211,4 +215,3 @@ class DAQConfiguration:
             cur_configs = DAQConfiguration.loadConfigs()
             del cur_configs[name]
             sh.store('daqconfigs', cur_configs)
-
diff --git a/lasp/device/lasp_rtaudio.pyx b/lasp/device/lasp_rtaudio.pyx
index 6232366..51ea6d8 100644
--- a/lasp/device/lasp_rtaudio.pyx
+++ b/lasp/device/lasp_rtaudio.pyx
@@ -714,6 +714,7 @@ cdef class RtAudio:
     def stop(self):
         if self.sd is NULL:
             raise RuntimeError('Stream is not running')
+
         try:
             self._rtaudio.stopStream()
             self._rtaudio.closeStream()
@@ -721,11 +722,9 @@ cdef class RtAudio:
             print(e)
             pass
         self.cleanupStream(self.sd)
+        self.sd = NULL
 
     cdef cleanupStream(self, PyStreamData* stream):
-        # printf('Entrance function cleanupStream...\n')
-        cdef:
-            void* ptr
         if stream == NULL:
             return
 
diff --git a/lasp/lasp_avstream.py b/lasp/lasp_avstream.py
index 03535a0..6ffdaf0 100644
--- a/lasp/lasp_avstream.py
+++ b/lasp/lasp_avstream.py
@@ -109,7 +109,6 @@ class AvStream:
         self._videothread = None
 
         self._audiobackend = RtAudio(daqconfig.api)
-        self.blocksize, self.samplerate = self._audiobackend.openStream(self)
 
     def nCallbacks(self):
         """Returns the current number of installed callbacks."""
@@ -148,7 +147,8 @@ class AvStream:
             self._videothread.start()
         else:
             self._video_started <<= True
-        self._audiobackend.start()
+
+        self.blocksize, self.samplerate = self._audiobackend.start(self)
 
     def _videoThread(self):
         cap = cv.VideoCapture(self._video)