diff --git a/youtube_dl/extractor/generic.py b/youtube_dl/extractor/generic.py
index f28a65d9b..26de27a7e 100644
--- a/youtube_dl/extractor/generic.py
+++ b/youtube_dl/extractor/generic.py
@@ -1317,7 +1317,7 @@ class GenericIE(InfoExtractor):
         first_bytes = full_response.read(512)
 
         # Is it an M3U playlist?
-        if first_bytes.startswith('#EXTM3U'):
+        if first_bytes.startswith(b'#EXTM3U'):
             info_dict['formats'] = self._extract_m3u8_formats(url, video_id, 'mp4')
             return info_dict