All of a sudden, a bunch -- but not all -- of my titles in my prs-600 changed from English to Chinese characters. I can't tell exactly when it happened. It only happened to a few. The titles only are affected; the content is just fine.
I use calibre to manage my elibrary. There, the affected titles also show as Chinese on the reader, but not in the main library. So it is clearly a problem with how the reader is displaying the titles, and not an actual corruption in the ebook files themselves.
Can anyone suggest how to clear this problem? And if this is a known issue, I'd very very interesting in knowing the cause so I can avoid the problem in the future.