I'm playing various MPEG2/TS streams using ProgressiveMediaSource. These streams have embedded CEA-608 and/or 708 captions, but not all of the streams display captions with ExoPlayer. I've ran them through other media players and verified they display captions.

I'm not attempting to modify the caption display at all, just enable them with default settings. I'm using a track selector:

DefaultTrackSelector trackSelector = new DefaultTrackSelector(this);
trackSelector.setParameters(
		trackSelector.buildUponParameters()
				.setPreferredTextLanguage("en")
				.setSelectUndeterminedTextLanguage(true)
);

Works great for some streams, and for DASH with TTML subtitles, but not for all streams with embedded 708 captions. Do I need more steps to enable CEA captioning?

I'm using ExoPlayer v 2.16.1; I tried 2.17.1 as well.