Comics jump to TOC

[klikklak]

Right, I didn't see this on the first page so I'm asking (apologies if there's already a gazillion threads about this).

When reading a comic, mobi format converted with calibre, I get a few pages ok, then it randomly jumps to the last page of the book, the TOC. Is there something I can do about this? It's highly annoying and really takes the joy of reading from this otherwise ok device. I think pdf's might be affected too, but haven't checked. I figured it was because of too large files, but the one I'm reading now is only 3-4MiB each file. Shouldn't be too much, right? I also tried tightening the screws and rebooting when it started doing it. Neither helped.

Thanks in advance and I hope the advise won't be that it's not fixable.