Fix to alternate version playback

source/Main.brs

@@ -202,13 +202,13 @@ sub Main (args as dynamic) as void
                 end if
 
                 ' Check to see if a specific video "version" was selected
+                mediaSourceId = invalid
                 if group.selectedVideoStreamId <> invalid
-                    video_id = group.selectedVideoStreamId
-                else
-                    video_id = group.id
+                    mediaSourceId = group.selectedVideoStreamId
                 end if
+                video_id = group.id
 
-                video = CreateVideoPlayerGroup(video_id, audio_stream_idx)
+                video = CreateVideoPlayerGroup(video_id, mediaSourceId, audio_stream_idx)
                 if video <> invalid
                     sceneManager.callFunc("pushScene", video)
                 end if

source/ShowScenes.brs

@@ -373,9 +373,9 @@ sub CreateSidePanel(buttons, options)
     group.options = options
 end sub
 
-function CreateVideoPlayerGroup(video_id, audio_stream_idx = 1)
+function CreateVideoPlayerGroup(video_id, mediaSourceId = invalid, audio_stream_idx = 1)
     ' Video is Playing
-    video = VideoPlayer(video_id, audio_stream_idx)
+    video = VideoPlayer(video_id, mediaSourceId, audio_stream_idx)
     if video = invalid then return invalid
     video.observeField("selectSubtitlePressed", m.port)
     video.observeField("state", m.port)

source/VideoPlayer.brs

@@ -1,9 +1,9 @@
-function VideoPlayer(id, audio_stream_idx = 1, subtitle_idx = -1)
+function VideoPlayer(id, mediaSourceId = invalid, audio_stream_idx = 1, subtitle_idx = -1)
 
     ' Get video controls and UI
     video = CreateObject("roSGNode", "JFVideo")
     video.id = id
-    AddVideoContent(video, audio_stream_idx, subtitle_idx)
+    AddVideoContent(video, mediaSourceId, audio_stream_idx, subtitle_idx)
 
     if video.content = invalid
         return invalid
@@ -16,7 +16,7 @@ function VideoPlayer(id, audio_stream_idx = 1, subtitle_idx = -1)
     return video
 end function
 
-sub AddVideoContent(video, audio_stream_idx = 1, subtitle_idx = -1, playbackPosition = -1)
+sub AddVideoContent(video, mediaSourceId, audio_stream_idx = 1, subtitle_idx = -1, playbackPosition = -1)
 
     video.content = createObject("RoSGNode", "ContentNode")
 
@@ -64,12 +64,15 @@ sub AddVideoContent(video, audio_stream_idx = 1, subtitle_idx = -1, playbackPosi
     video.content.PlayStart = int(playbackPosition / 10000000)
 
     ' Call PlayInfo from server
-    mediaSourceId = video.id
+    if mediaSourceId = invalid
+        mediaSourceId = video.id
+    end if
     if meta.live then mediaSourceId = "" ' Don't send mediaSourceId for Live media
+
     playbackInfo = ItemPostPlaybackInfo(video.id, mediaSourceId, audio_stream_idx, subtitle_idx, playbackPosition)
 
     video.videoId = video.id
-    video.mediaSourceId = video.id
+    video.mediaSourceId = mediaSourceId 
     video.audioIndex = audio_stream_idx
 
     if playbackInfo = invalid
@@ -112,6 +115,9 @@ sub AddVideoContent(video, audio_stream_idx = 1, subtitle_idx = -1, playbackPosi
             "PlaySessionId": video.PlaySessionId,
             "AudioStreamIndex": audio_stream_idx
         })
+        if mediaSourceId <> ""
+            params.MediaSourceId = mediaSourceId
+        end if
         video.content.url = buildURL(Substitute("Videos/{0}/stream", video.id), params)
         video.isTranscoded = false
         video.audioTrack = (audio_stream_idx + 1).ToStr() ' Roku's track indexes count from 1. Our index is zero based

source/utils/Subtitles.brs

@@ -49,7 +49,7 @@ sub changeSubtitleDuringPlayback(newid)
 
         ' Switching to Encoded Subtitle stream
         video.control = "stop"
-        AddVideoContent(video, video.audioIndex, newSubtitles.Index, video.position * 10000000)
+        AddVideoContent(video, video.mediaSourceId, video.audioIndex, newSubtitles.Index, video.position * 10000000)
         video.control = "play"
         video.globalCaptionMode = "Off" ' Using encoded subtitles - so turn off text subtitles
 
@@ -57,7 +57,7 @@ sub changeSubtitleDuringPlayback(newid)
 
         ' Switching from an Encoded stream to a text stream
         video.control = "stop"
-        AddVideoContent(video, video.audioIndex, -1, video.position * 10000000)
+        AddVideoContent(video, video.mediaSourceId, video.audioIndex, -1, video.position * 10000000)
         video.control = "play"
         video.globalCaptionMode = "On"
         video.subtitleTrack = video.availableSubtitleTracks[newSubtitles.TextIndex].TrackName
@@ -82,7 +82,7 @@ sub turnoffSubtitles()
     ' Check if Enoded subtitles are being displayed, and turn off
     if current > -1 and video.Subtitles[current].IsEncoded
         video.control = "stop"
-        AddVideoContent(video, video.audioIndex, -1, video.position * 10000000)
+        AddVideoContent(video, video.mediaSourceId, video.audioIndex, -1, video.position * 10000000)
         video.control = "play"
     end if
 end sub