I have that happening as well. For my system, removing our Thunderbolt connected Redrocket has solved the issue. If there is no RedRocket connected via our Sonnet enclosure, all of the R3D files show up just fine. If our RedRocket is connected, a random half of the R3D files are either black in the viewer/thumbnails or don’t register as R3D files at all, just folders.
That’s as far as we could figure out at the moment. I’d love to know if anyone has a fix.
🙂