diff --git a/src/calibre/devices/kobo/driver.py b/src/calibre/devices/kobo/driver.py
index 5e00d0c907..9bd21b1665 100644
--- a/src/calibre/devices/kobo/driver.py
+++ b/src/calibre/devices/kobo/driver.py
@@ -1348,6 +1348,8 @@ class KOBOTOUCH(KOBO):
     EXTRA_CUSTOMIZATION_MESSAGE = []
     EXTRA_CUSTOMIZATION_DEFAULT = []
 
+    OSX_MAIN_MEM_VOL_PAT = re.compile(r'/KOBOeReader')
+
     opts = None
 
     TIMESTAMP_STRING = "%Y-%m-%dT%H:%M:%SZ"
@@ -1449,7 +1451,29 @@ class KOBOTOUCH(KOBO):
 
     def open_linux(self):
         super(KOBOTOUCH, self).open_linux()
+        
+        self.swap_drives_if_needed()
 
+    def open_osx(self):
+        # Just dump some info to the logs.
+        super(KOBOTOUCH, self).open_osx()
+
+        # Wrap some debugging output in a try/except so that it unlikely to break things completely. 
+        try:        
+            if DEBUG:
+                from calibre.constants import plugins
+                usbobserver, usbobserver_err = plugins['usbobserver']
+                mount_map = usbobserver.get_mounted_filesystems()
+                debug_print('KoboTouch::open_osx - mount_map=', mount_map)
+                debug_print('KoboTouch::open_osx - self._main_prefix=', self._main_prefix)
+                debug_print('KoboTouch::open_osx - self._card_a_prefix=', self._card_a_prefix)
+                debug_print('KoboTouch::open_osx - self._card_b_prefix=', self._card_b_prefix)
+        except:
+            pass
+
+        self.swap_drives_if_needed()
+
+    def swap_drives_if_needed(self):
         # Check the drives have been mounted as expected and swap if needed.
         if self._card_a_prefix is None:
             return
@@ -1459,9 +1483,6 @@ class KOBOTOUCH(KOBO):
             self._main_prefix = self._card_a_prefix
             self._card_a_prefix = temp_prefix
 
-    def osx_sort_names(self, names):
-        return self.sort_drives(names)
-
     def windows_sort_drives(self, drives):
         return self.sort_drives(drives)
 
@@ -1471,13 +1492,13 @@ class KOBOTOUCH(KOBO):
         main = drives.get('main', None)
         carda = drives.get('carda', None)
         if main and carda and not self.is_main_drive(main):
-            debug_print('KoboTouch::windows_sort_drives - main=%s, carda=%s' % (main, carda))
             drives['main'] = carda
             drives['carda'] = main
+            debug_print('KoboTouch::sort_drives - swapped drives - main=%s, carda=%s' % (drives['main'], drives['carda']))
         return drives
 
     def is_main_drive(self, drive):
-        debug_print('KoboTouch::is_main_drive - main_drive=%s, path=%s' % (drive, os.path.join(drive, '.kobo')))
+        debug_print('KoboTouch::is_main_drive - drive=%s, path=%s' % (drive, os.path.join(drive, '.kobo')))
         return os.path.exists(self.normalize_path(os.path.join(drive, '.kobo')))
 
     def books(self, oncard=None, end_session=True):