I have a similar problem riping BD discs into mkv using makemkv. If i play the BD DISC with Powerdvd it will show DTS-HD MA however if i rip that disc into mkv, and i do select the DTS-MA track, when playing it shows a different name on the information tab, it will say DTS 7.1. But i know its playing HD content because of the bitrate, which is around 6k on avg. So my guess is that there is an issue with the way the audio tracks gets tagged when it gets converted to mkv.
P.S: I tried DVDFAB also and did the same thing.
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