diff --git a/mscore/pm.cpp b/mscore/pm.cpp
index 486f2922e7a74..dfb98df8527bd 100644
--- a/mscore/pm.cpp
+++ b/mscore/pm.cpp
@@ -51,10 +51,18 @@ PortMidiDriver::PortMidiDriver(Seq* s)
 
 PortMidiDriver::~PortMidiDriver()
       {
+      if (timer) {
+            timer->stop();
+            delete timer;
+            }
       if (inputStream) {
             Pt_Stop();
             Pm_Close(inputStream);
             }
+      if (outputStream) {
+            Pt_Stop();
+            Pm_Close(outputStream);
+            }
       }
 
 //---------------------------------------------------------
@@ -64,41 +72,38 @@ PortMidiDriver::~PortMidiDriver()
 
 bool PortMidiDriver::init()
       {
-      inputId = getDeviceIn(preferences.getString(PREF_IO_PORTMIDI_INPUTDEVICE));
-      if (inputId == -1)
-            inputId  = Pm_GetDefaultInputDeviceID();
-
-      if (inputId == pmNoDevice)
-            return false;
-
+      inputId = getDeviceIn(preferences.getString(PREF_IO_PORTMIDI_INPUTDEVICE)); // Note: allow init even if inputId == pmNoDevice, in case of output
       outputId = getDeviceOut(preferences.getString(PREF_IO_PORTMIDI_OUTPUTDEVICE)); // Note: allow init even if outputId == pmNoDevice, since input is more important than output.
-
+      if ((inputId == -1) && (preferences.getString(PREF_IO_PORTMIDI_INPUTDEVICE) != " "))
+            inputId = Pm_GetDefaultInputDeviceID();
+      if ((inputId == pmNoDevice) && (outputId == pmNoDevice))
+            return false;
       static const int DRIVER_INFO = 0;
       static const int TIME_INFO = 0;
 
       Pt_Start(20, 0, 0);      // timer started, 20 millisecond accuracy
 
-      PmError error = Pm_OpenInput(&inputStream,
-         inputId,
-         (void*)DRIVER_INFO,
-         preferences.getInt(PREF_IO_PORTMIDI_INPUTBUFFERCOUNT),
-         ((PmTimeProcPtr) Pt_Time),
-         (void*)TIME_INFO);
-      if (error != pmNoError) {
-            const char* p = Pm_GetErrorText(error);
-            qDebug("PortMidi: open input (id=%d) failed: %s", int(inputId), p);
-            Pt_Stop();
-            return false;
+      if (inputId != pmNoDevice) {
+            PmError error = Pm_OpenInput(&inputStream,
+               inputId,
+               (void*)DRIVER_INFO,
+               preferences.getInt(PREF_IO_PORTMIDI_INPUTBUFFERCOUNT),
+               ((PmTimeProcPtr) Pt_Time),
+               (void*)TIME_INFO);
+            if (error != pmNoError) {
+                  const char* p = Pm_GetErrorText(error);
+                  qDebug("PortMidi: open input (id=%d) failed: %s", int(inputId), p);
+                  Pt_Stop();
+                  return false;
+                  }
+            Pm_SetFilter(inputStream, PM_FILT_ACTIVE | PM_FILT_CLOCK | PM_FILT_SYSEX);
+            PmEvent buffer[1];
+            while (Pm_Poll(inputStream))
+                  Pm_Read(inputStream, buffer, 1);
             }
 
-      Pm_SetFilter(inputStream, PM_FILT_ACTIVE | PM_FILT_CLOCK | PM_FILT_SYSEX);
-
-      PmEvent buffer[1];
-      while (Pm_Poll(inputStream))
-            Pm_Read(inputStream, buffer, 1);
-
       if (outputId != pmNoDevice) {
-            error = Pm_OpenOutput(&outputStream,
+            PmError error = Pm_OpenOutput(&outputStream,
                outputId,
                (void*)DRIVER_INFO,
                preferences.getInt(PREF_IO_PORTMIDI_OUTPUTBUFFERCOUNT),
diff --git a/mscore/pm.h b/mscore/pm.h
index 69339dd35a8cf..3f5544003c522 100644
--- a/mscore/pm.h
+++ b/mscore/pm.h
@@ -62,6 +62,7 @@ class PortMidiDriver : public MidiDriver {
       PmStream* getOutputStream() { return outputStream; }
       bool canOutput() { return outputStream != 0; }
       bool isSameCoreMidiIacBus(const QString& inInterfaceAndName, const QString& outInterfaceAndName);
+      int inputId() { return inputId }
       };
 
 
diff --git a/mscore/prefsdialog.cpp b/mscore/prefsdialog.cpp
index 374bbf4f05678..1781b56f893a1 100644
--- a/mscore/prefsdialog.cpp
+++ b/mscore/prefsdialog.cpp
@@ -450,12 +450,20 @@ void PreferenceDialog::updateValues(bool useDefaultValues)
                   PortMidiDriver* midiDriver = static_cast<PortMidiDriver*>(audio->mididriver());
                   if (midiDriver) {
                         QStringList midiInputs = midiDriver->deviceInList();
-                        int curMidiInIdx = 0;
+                        int curMidiInIdx = -1;
                         portMidiInput->clear();
+                        portMidiInput->addItem(" ", -1); // note: a space to be different from the default empty string.
+                        // The current input device can be different from the saved preference if the preference was empty
+                        // because of automatic grabbing of the default input device if not explicitly told otherwise.
+                        // Therefore, comparison must be done with respect to the actual current input device name.
+                        const PmDeviceInfo* info = Pm_GetDeviceInfo(midiDriver->inputId());
+                        QString portmidiInputDevice;
+                        if(info && (info->input))
+                              portmidiInputDevice = QString(info->interf) + "," + QString(info->name);
                         for(int i = 0; i < midiInputs.size(); ++i) {
                               portMidiInput->addItem(midiInputs.at(i), i);
-                              if (midiInputs.at(i) == preferences.getString(PREF_IO_PORTMIDI_INPUTDEVICE))
-                                    curMidiInIdx = i;
+                              if (midiInputs.at(i) == portmidiInputDevice)
+                                    curMidiInIdx = i + 1;
                               }
                         portMidiInput->setCurrentIndex(curMidiInIdx);