Failure to play when video has multiple streams with same name

Jan 31, 2012 at 11:46 AM
Edited Jan 31, 2012 at 12:08 PM

I have a video that has a caption stream named "English" and an audio stream named "English". This does not play using SMF but plays fine using a plain SSME. As soon as I change the names to be different, it starts working in SMF, as well.

I am not seeing any exceptions in the debugger - the video simply does not play. I can see with Fiddler that before it stops, one or two requests are made for the first fragments of the first two channels (audio and video), whereas no requests are made for the caption channel.

Since debugging does not show me any errors, I am not sure where to dig for a fix. Is this a known issue? Can it be fixed easily?

Edit: it appears that the order of streams in the client manifest is relevant. The issue only occurs if the caption stream is listed before the audio stream.

Here is a set of videos that demonstrate the issue (same video, modified client manifest):

Original (does not play): http://media.axprod.net/Axinom/TechnicalExamples/Smf/Sintel-3min.ism/Manifest

Stream order switched around (audio before text; plays): http://media.axprod.net/Axinom/TechnicalExamples/Smf/Sintel-3min-switched.ism/Manifest

Names unique (plays): http://media.axprod.net/Axinom/TechnicalExamples/Smf/Sintel-3min-names.ism/Manifest