No. They don't need to be transcoded at all, they're natively supported MP4 files. I've even tried it with my natively supported h.265 MP4s. It appears that the Mezzmo Android app is crashing in some way. It "crashes" out of the movie back to the selection screen where all of the movies are listed. The previous version of the AndroidTV app didn't do this, so whatever is causing it is new, or it just never triggered.
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