GoldVortex SLR seems to have modified all or part of its HEVC videos to MKV with OPUS audio.
It's the OPUS codec that seems to be the problem (before VirtualRealPorn switched to HEVC, they were on VP9 with OPUS audio and these videos also have no sound, so they have to re-encode the audio).
I don't have a Quest 2 (I'm on gear vr with a note 8) and I don't have the latest version of DEOVR (stuck in 8.53), but I have the impression that the problem is generalized to all independent headsets.
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