Oh man I feel this, got burned the same way on a box set last year and now I'm paranoid about it too. Quickest trick I've found is to just skip to like the 3 minute mark and check one line against what you're hearing, if the words don't line up you know right away. Some discs also label the track as "English SDH" or "for the dub" so I scan the menu for that before I even hit play.

47 shows? That is wild. Having that many things waiting for you would just make me freeze up and watch nothing at all. I bet half of those never even get opened once.

Also check it at different rack spots since my top ran hot while the bottom sat 40 low.