I assume you are the person who asked on the calibre bug forum...
We will need a CC debug log from the failing device and a calibre debug log from your linux device. See our FAQ answer
How do I get help? Please erase the multipie email address, as you are dealing directly with me (the other address). Either post the calibre log here (in SPOILER tags) or send it to the same email address as the CC debug log.
Just a guess: I suspect that the problem is caused by a corrupted device cache on the calibre machine. The debug logs should help determine if this is the case.
Oh, and by any chance have you installed any "security software" on the memopad?