Audiobook does not resume from last position

Hi,

I have a new 4th generation iPod shuffle to which I have added 2 music playlists and one audiobook, which is divided into 2 physical files and 15 chapters across those 2 files.

Whenever I switch away from the audiobook to listen to music and then try to listen to the audiobook again, it always resumes at the beginning of chapter 10, regardless of where I last paused it (whether in chapter 10 or chapter 1).

The shuffle is in 'play in order' mode just in case, but that makes no difference.

I've also changed in iTunes that for the two audio book files the media kind is set to 'audiobook' and 'remember playback position' is ticked.

The only reason I bought the shuffle is that I read it played nicely with Audible books. What am I doing wrong? I haven't used an iPod before so hopefully I've just missed something obvious. Thanks in advance!