diff --git a/autosub/__init__.py b/autosub/__init__.py
index 61019464b..a6c560ab5 100644
--- a/autosub/__init__.py
+++ b/autosub/__init__.py
@@ -233,6 +233,16 @@ def generate_subtitles( # pylint: disable=too-many-locals,too-many-arguments
     """
     Given an input audio/video file, generate subtitles in the specified language and format.
     """
+    if os.name != "nt" and "Darwin" in os.uname():
+        #the default unix fork method does not work on Mac OS
+        #need to use forkserver
+        try:
+            if 'forkserver' not in multiprocessing.get_start_method(allow_none=True):
+                multiprocessing.set_start_method('forkserver')
+        except AttributeError:
+            # for python 2 not have set_start_method... cannot be used on mac
+            print("Python 2 fork() does not work on MacOS. Please use Python 3 instead.")
+
     audio_filename, audio_rate = extract_audio(source_path)
 
     regions = find_speech_regions(audio_filename)