The error message, though not the error code, is the same as I saw a while ago with our Dell LTO 1 library. If I remember correctly, after trying a variety of things I spoke to Dell Support, and we determined that it was actually a hardware fault. Unfortunately I can't remember what the actual fault was, but I believe it turned out to be a small component connected with the changer mechanism had failed, so they replaced it.
I would suggest you contact the relevant support people connected with your library, as that may be where the problem is.