diff --git a/src/calibre/devices/mtp/unix/driver.py b/src/calibre/devices/mtp/unix/driver.py
index 338913114f..2f215f6353 100644
--- a/src/calibre/devices/mtp/unix/driver.py
+++ b/src/calibre/devices/mtp/unix/driver.py
@@ -27,7 +27,8 @@ def fingerprint(d):
 
 class MTP_DEVICE(MTPDeviceBase):
 
-    supported_platforms = ['linux', 'osx']
+    # libusb(x) does not work on OS X. So no MTP support for OS X
+    supported_platforms = ['linux']
 
     def __init__(self, *args, **kwargs):
         MTPDeviceBase.__init__(self, *args, **kwargs)
diff --git a/src/calibre/devices/scanner.py b/src/calibre/devices/scanner.py
index 6865546a54..e0bb74fa2a 100644
--- a/src/calibre/devices/scanner.py
+++ b/src/calibre/devices/scanner.py
@@ -292,7 +292,15 @@ if islinux:
 
 libusb_scanner = LibUSBScanner()
 if isosx:
-    osx_scanner = libusb_scanner
+    # Apparently libusb causes mem leaks on some Macs and hangs on others and
+    # works on a few. OS X users will just have to live without MTP support.
+    # See https://bugs.launchpad.net/calibre/+bug/1044706
+    # See https://bugs.launchpad.net/calibre/+bug/1044758
+    # osx_scanner = libusb_scanner
+    usbobserver, usbobserver_err = plugins['usbobserver']
+    if usbobserver is None:
+        raise RuntimeError('Failed to load usbobserver: %s'%usbobserver_err)
+    osx_scanner = usbobserver.get_usb_devices
 
 if isfreebsd:
     freebsd_scanner = FreeBSDScanner()