Audible Book Chapters Not Synced to iPod Shuffle Since Catalina Upgrade

Hello

I recently upgraded to Catalina and have found when I sync Audible audio books to my iPod shuffle 4th Gen (now using the Finder rather than iTunes) the chapters do not sync. The books is synced ok and plays but only as a single massive track.

I use the iPod for running and if I accidentally nudge Next or Previous the whole book is skipped. For long books ~14 hours this is unworkable. I even left the iPod playing for over 5 hours using a stop watch to try and get back to where I was only to accidentally click the previous button the next day!

Does anyone else have this issue, can anyone suggest any fixes.

Many thanks