diff --git a/cmake/cpack/deploy_mac.cmake.in b/cmake/cpack/deploy_mac.cmake.in
index 02ef1b89c..eb98aa09c 100644
--- a/cmake/cpack/deploy_mac.cmake.in
+++ b/cmake/cpack/deploy_mac.cmake.in
@@ -25,6 +25,12 @@ foreach(RPATH_DIR ${EXTERNAL_LIB_DIRS})
   execute_process(COMMAND /usr/bin/install_name_tool -add_rpath ${RPATH_DIR} ${CPACK_TEMPORARY_INSTALL_DIRECTORY}/SDRangel.app/Contents/MacOS/SDRangel)
 endforeach()
 
+
+execute_process ( COMMAND "checking signature" )
+execute_process ( COMMAND codesign -vv ${EXTERNAL_LIB_DIRS}/libusb-1.0.0.dylib )
+execute_process ( COMMAND md5sum -vv ${EXTERNAL_LIB_DIRS}/libusb-1.0.0.dylib )
+execute_process ( COMMAND "signature checked" )
+
 # Add RPATH to libraries in build directory
 foreach(RPATH_DIR_1 ${EXTERNAL_LIB_DIRS})
   file(GLOB LIBS_TO_FIX  ${RPATH_DIR_1}/*.dylib)
@@ -40,3 +46,8 @@ endforeach()
 # Run macdeployqt which should copy all libraries and frameworks and Qt plugins and qml
 message ("Running macdeployqt in ${CPACK_TEMPORARY_INSTALL_DIRECTORY}")
 execute_process ( COMMAND macdeployqt ${CPACK_TEMPORARY_INSTALL_DIRECTORY}/SDRangel.app -no-strip -always-overwrite -verbose=1 -qmldir=@CMAKE_CURRENT_SOURCE_DIR@/../../plugins/ )
+
+execute_process ( COMMAND "checking signature" )
+execute_process ( COMMAND codesign -vv ${CPACK_TEMPORARY_INSTALL_DIRECTORY}/SDRangel.app/Contents/Frameworks/libusb-1.0.0.dylib )
+execute_process ( COMMAND md5sum -vv ${CPACK_TEMPORARY_INSTALL_DIRECTORY}/SDRangel.app/Contents/Frameworks/libusb-1.0.0.dylib )
+execute_process ( COMMAND "signature checked" )
diff --git a/external/CMakeLists.txt b/external/CMakeLists.txt
index 0d6b438cc..80882bedb 100644
--- a/external/CMakeLists.txt
+++ b/external/CMakeLists.txt
@@ -232,8 +232,11 @@ if (NOT LIBUSB_FOUND AND NOT USE_PRECOMPILED_LIBS)
         set(LIBUSB_LIBRARIES "${install_dir}/lib/libusb-1.0${CMAKE_SHARED_LIBRARY_SUFFIX}" CACHE INTERNAL "")
         set(MACOS_EXTERNAL_LIBS_FIXUP "${MACOS_EXTERNAL_LIBS_FIXUP};${install_dir}/lib")
         add_custom_command(TARGET libusb POST_BUILD
-                    COMMAND codesign --verify "${install_dir}/lib/libusb-1.0${CMAKE_SHARED_LIBRARY_SUFFIX}"
+                    COMMAND codesign -vv "${install_dir}/lib/libusb-1.0${CMAKE_SHARED_LIBRARY_SUFFIX}"
                     COMMENT "checking signature on libusb")
+        add_custom_command(TARGET libusb POST_BUILD
+                    COMMAND md5sum "${install_dir}/lib/libusb-1.0${CMAKE_SHARED_LIBRARY_SUFFIX}"
+                    COMMENT "md5sum for libusb")
     endif ()
 endif (NOT LIBUSB_FOUND AND NOT USE_PRECOMPILED_LIBS)