I'm following "Coding Together: Developing Apps for iPhone and iPad (Winter 2013)" and when I tried to watch on iPad I could not enable subtitle, but in the last "season" closed caption works fine.
I'm not sure, but I believe that the issue is with the kind of subtitle: This season is with 3GPP subtitle and the old one was Closed Caption.
The point is: Why does iTunes U don't use the infrastructure of the video player?
I have this problem too. The strange thing is that I airplayed the same course to my apple tv and it displayed fine the subtitles... SomI think it is an issue with itunes u app. Hope apple get this fixed as soon as possible.
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