I've been having a re-occurring problem reading data from self-burnt data Blu-ray discs. I'll try to copy the contents of a disc to an external HD and nearly every time, at some point during the copy, I'll get a -36 Error code from the Finder (data can't be read or written).
Just before this error the drive spins down and I can hear the head jumping around, like it's having trouble finding data. The drive will do that for between 2-10+ minutes before giving up finally and showing me the error code.
This tends to happen on similar types of file – usually files that are packages (Logic files, Photos library), Logic project backups and EXS24 sample files (AIFs). Sometimes copying that file again works, sometimes not.
These discs were originally burnt through the Finder and they all passed post-burn verification. So the question is: where might the problem be? Is it the OS? Is it the drive? Is it the discs? Really I have no answer.
(I'm running fully updated Mac OS 10.10.5, Blu-ray drive is a Samsung SE-506, discs are TDK-branded light blue face.)