I've been in touch with Ulrich. Seems to be just a hardware issue--possibly a bad cable.
View QuestionSeth Goldin | Answers
Is it possible to use TentacleSync software to update the file timecode on XAVC without transcoding?
Just figured this out. Just by exporting audio and video as "pass-through," the XAVC is re-wrapped from MXF into MOV, with updated timecode. Everything's working well!
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