Potemayo ep 5 is the latest. Haganai ep 7 won't display subtitles. MKV files seem to fail the most often, and AVI work the best. Guess which format most of this anime was released in.
All of these are encoding problems, though. If I could find them in different formats, that might fix it.
...good luck with finding stuff that was fansubbed and forgotten five years ago, though.
I should add that the PC had no trouble playing any of this stuff. With the exception of Haganai all these things are rewatch material for me, and they all ran just fine from the computer. It's a shame that Samsung couldn't incorporate a more robust set of video codecs in the BD player, but I have to admit the set they have in there now is pretty damned good.
I was about half convinced that soft subtitles would be a major problem for the thing, but they just worked, at least until I got to ep 7 of Haganai. The fact that the player can handle soft subtitles at all--and does so both automatically and correctly, at least most of the time--is pretty impressive to me. (Yes, I tried turning the subtitles on with ep 7. No, it didn't work.)
So, I find it mildly frustrating that these series won't play in their entirety, but I can't lay the blame squarely on the player. Some episodes just weren't encoded properly, and if the fansubbers had been consistent in their methods, series that start out playing fine would play correctly in their entirety.
That's how it goes, though. I didn't buy the BD player to play anime digisubs; I bought it to play BD disks, and this capability is a welcome and cool bonus. I therefore am keeping my perspective about this, because it really is damned cool.