Hi! Thanks for that. Here is a pdf that had the problem:
https://drive.google.com/file/d/0B-0...it?usp=sharing
I've just done a factory resent on my device and am now setting it up again. Maybe the problem will be fixed now. We'll see. I'm still curious though, why only some pdfs weren't working before. Let me know if you come up with anything for this one.
Thank you!