diff --git a/cerbero/tools/osxuniversalgenerator.py b/cerbero/tools/osxuniversalgenerator.py
index 08f90ca9d6d77338bd7d4898356fc06daae209c7..31bd9ac0856881fab0bf0c4fa0c65acf77113070 100644
--- a/cerbero/tools/osxuniversalgenerator.py
+++ b/cerbero/tools/osxuniversalgenerator.py
@@ -119,7 +119,7 @@ class OSXUniversalGenerator(object):
 
     def get_file_type(self, filepath):
         cmd = '%s -bh "%s"' % (self.FILE_CMD, filepath)
-        return self._call(cmd)[0:-1] #remove trailing \n
+        return self._call(cmd)[:-1] #remove trailing \n
 
     def _detect_merge_action(self, files_list):
         actions = []
@@ -228,14 +228,7 @@ class OSXUniversalGenerator(object):
 
     def _call(self, cmd, cwd=None):
         cmd = cmd or self.root
-        process = subprocess.Popen(cmd, cwd=cwd,
-            stdout=subprocess.PIPE, shell=True)
-        output, unused_err = process.communicate()
-
-        if sys.stdout.encoding:
-            output = output.decode(sys.stdout.encoding)
-
-        return output
+        return shell.check_call(cmd, cmd_dir=cwd, split=False, shell=True)
 
 
 class Main(object):
diff --git a/cerbero/utils/shell.py b/cerbero/utils/shell.py
index f684ab5bcea3173aac7248d9498e73d95ce0b9ab..9183b6e6cdb2e2291d87553958d9c6b4857805db 100644
--- a/cerbero/utils/shell.py
+++ b/cerbero/utils/shell.py
@@ -193,7 +193,7 @@ def check_call(cmd, cmd_dir=None, shell=False, split=True, fail=False, env=None)
         raise FatalError(_("Error running command: %s") % cmd)
 
     if sys.stdout.encoding:
-        output = output.decode(sys.stdout.encoding)
+        output = output.decode(sys.stdout.encoding, errors='replace')
 
     return output