diff --git a/bin/ffx/media_descriptor.py b/bin/ffx/media_descriptor.py
index cab7054..8f09d76 100644
--- a/bin/ffx/media_descriptor.py
+++ b/bin/ffx/media_descriptor.py
@@ -8,7 +8,7 @@ class MediaDescriptor():
     """This class represents the structural content of a media file including streams and metadata"""
 
     TAGS_KEY = 'tags'
-    TRACK_DESCRIPTORS_KEY = 'track_descriptors'
+    TRACK_DESCRIPTOR_LIST_KEY = 'track_descriptors'
     CLEAR_TAGS_KEY = 'clear_tags'
 
     FFPROBE_DISPOSITION_KEY = 'disposition'
@@ -25,18 +25,18 @@ class MediaDescriptor():
         else:
                 self.__mediaTags = {}
 
-        if MediaDescriptor.TRACK_DESCRIPTORS_KEY in kwargs.keys():
+        if MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY in kwargs.keys():
                 # if type(kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY]) is not List[TrackDescriptor]: # Use List typehint for TrackDescriptor as well if it works
                 #         raise TypeError(f"MediaDescriptor.__init__(): Argument {MediaDescriptor.TRACK_DESCRIPTORS_KEY} is required to be of type list containing only elements of type TrackDescriptor")
 
-                if type(kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY]) is not dict: # Use List typehint for TrackDescriptor as well if it works
-                        raise TypeError(f"MediaDescriptor.__init__(): Argument {MediaDescriptor.TRACK_DESCRIPTORS_KEY} is required to be of type dict")
-                # for d in kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY]:
-                #         if type(d) is not TrackDescriptor:
-                #                 raise TypeError(f"TrackDesciptor.__init__(): All elements of argument set {MediaDescriptor.TRACK_DESCRIPTORS_KEY} is required to be of type TrackDescriptor")
-                self.__trackDescriptors = kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY]
+                if type(kwargs[MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY]) is not list: # Use List typehint for TrackDescriptor as well if it works
+                        raise TypeError(f"MediaDescriptor.__init__(): Argument {MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY} is required to be of type list")
+                for d in kwargs[MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY]:
+                        if type(d) is not TrackDescriptor:
+                                raise TypeError(f"TrackDesciptor.__init__(): All elements of argument list {MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY} are required to be of type TrackDescriptor")
+                self.__trackDescriptors = kwargs[MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY]
         else:
-                self.__trackDescriptors = set()
+                self.__trackDescriptors = []
 
         if MediaDescriptor.CLEAR_TAGS_KEY in kwargs.keys():
                 if type(kwargs[MediaDescriptor.CLEAR_TAGS_KEY]) is not bool:
@@ -49,23 +49,31 @@ class MediaDescriptor():
     @classmethod
     def fromFfprobe(cls, formatData, streamData):
 
-        trackDescriptors = {}
+        #trackDescriptors = {}
+
+        kwargs = {}
+
+        if MediaDescriptor.FFPROBE_TAGS_KEY in formatData.keys():
+              kwargs[MediaDescriptor.TAGS_KEY] = formatData[MediaDescriptor.FFPROBE_TAGS_KEY]
+
+        kwargs[MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY] = []
 
         for streamObj in streamData:
 
-            trackType = TrackType.fromLabel(streamObj[MediaDescriptor.FFPROBE_CODEC_TYPE_KEY])
+            #trackType = TrackType.fromLabel(streamObj[MediaDescriptor.FFPROBE_CODEC_TYPE_KEY])
 
-            if trackType != TrackType.UNKNOWN:
+#             if trackType != TrackType.UNKNOWN:
+# 
+#                 if trackType.label() not in trackDescriptors.keys():
+#                     trackDescriptors[trackType.label()] = []
+# 
+#                 trackDescriptors[trackType.label()].append(TrackDescriptor.fromFfprobe(streamObj))
 
-                if trackType.label() not in trackDescriptors.keys():
-                    trackDescriptors[trackType.label()] = []
+            if TrackType.fromLabel(streamObj[MediaDescriptor.FFPROBE_CODEC_TYPE_KEY]) != TrackType.UNKNOWN:
+                kwargs[MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY].append(TrackDescriptor.fromFfprobe(streamObj))
 
-                trackDescriptors[trackType.label()].append(TrackDescriptor.fromFfprobe(streamObj))
 
-        kwargs = {}
-        if MediaDescriptor.FFPROBE_TAGS_KEY in formatData.keys():
-              kwargs[MediaDescriptor.TAGS_KEY] = formatData[MediaDescriptor.FFPROBE_TAGS_KEY]
-        kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY] = trackDescriptors
+        # kwargs[MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY] = trackDescriptors
 
         return cls(**kwargs)
 
@@ -75,7 +83,9 @@ class MediaDescriptor():
 
 
     def getAudioTracks(self) -> List[TrackDescriptor]:
-        return self.__trackDescriptors[TrackType.AUDIO.label()] if TrackType.AUDIO.label() in self.__trackDescriptors.keys() else []
+        #return self.__trackDescriptors[TrackType.AUDIO.label()] if TrackType.AUDIO.label() in self.__trackDescriptors.keys() else []
+        return [d for d in self.__trackDescriptors if d.getType() == TrackType.AUDIO]
 
     def getSubtitleTracks(self) -> List[TrackDescriptor]:
-        return self.__trackDescriptors[TrackType.SUBTITLE.label()] if TrackType.SUBTITLE.label() in self.__trackDescriptors.keys() else []
+        #return self.__trackDescriptors[TrackType.SUBTITLE.label()] if TrackType.SUBTITLE.label() in self.__trackDescriptors.keys() else []
+        return [d for d in self.__trackDescriptors if d.getType() == TrackType.SUBTITLE]
diff --git a/bin/ffx/model/pattern.py b/bin/ffx/model/pattern.py
index 1fc1fa1..7742079 100644
--- a/bin/ffx/model/pattern.py
+++ b/bin/ffx/model/pattern.py
@@ -53,13 +53,16 @@ class Pattern(Base):
         kwargs = {}
         kwargs[MediaDescriptor.TAGS_KEY] = self.getTags()
         
-        kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY] = {}
+        kwargs[MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY] = []
 
-        for track in self.tracks:
-
-            if track.getType() not in kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY].keys():
-                kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY][track.getType().label()] = []
+#         for track in self.tracks:
+# 
+#             if track.getType() not in kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY].keys():
+#                 kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY][track.getType().label()] = []
+# 
+#             kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY][track.getType().label()].append(track.getDescriptor())
 
-            kwargs[MediaDescriptor.TRACK_DESCRIPTORS_KEY][track.getType().label()].append(track.getDescriptor())
+        for track in self.tracks:
+            kwargs[MediaDescriptor.TRACK_DESCRIPTOR_LIST_KEY].append(track.getDescriptor())
 
         return MediaDescriptor(**kwargs)