diff --git a/youtube_dl/extractor/cwtv.py b/youtube_dl/extractor/cwtv.py
index 1ab9333b2b..f4cf0f1c54 100644
--- a/youtube_dl/extractor/cwtv.py
+++ b/youtube_dl/extractor/cwtv.py
@@ -82,6 +82,11 @@ def _real_extract(self, url):
                             'url': quality_url,
                             'tbr': tbr,
                         })
+        video_metadata = video_data['assetFields']
+        ism_url = video_metadata.get('smoothStreamingUrl')
+        if ism_url:
+            formats.extend(self._extract_ism_formats(
+                ism_url, video_id, ism_id='mss', fatal=False))
         self._sort_formats(formats)
 
         thumbnails = [{
@@ -90,8 +95,6 @@ def _real_extract(self, url):
             'height': image.get('height'),
         } for image_id, image in video_data['images'].items() if image.get('uri')] if video_data.get('images') else None
 
-        video_metadata = video_data['assetFields']
-
         subtitles = {
             'en': [{
                 'url': video_metadata['UnicornCcUrl'],