Fix issue with providing arguments for check_call.

All arguments for subprocess.check_call() must be list of strings.

flac2ogg.py

@@ -14,7 +14,7 @@ from mutagen.mp3 import MP3
 from mutagen.easyid3 import EasyID3, EasyID3KeyError
 
 
-VERSION = '1.3'
+VERSION = '1.3.1'
 
 
 def match_file(path):
@@ -158,7 +158,7 @@ class OpusEncoder(Encoder):
             self.quality = 128
 
     def encode(self, input_fname, output_fname):
-        sp.check_call(["opusenc", "--bitrate", self.quality, input_fname,
+        sp.check_call(["opusenc", "--bitrate", str(self.quality), input_fname,
                        output_fname])