I use my 280R to play free downloaded library audio books. It has worked in the past but the last few days the library books (not the other music I have on it) have been stuck on “syncronize to continue your music subscription.” I do not have or want a music sub. Have tried everything I can think of.
Have you tried deleting and re-transfering the books? Are you sure they are DRM-free? It doesn’t sound like it.
Even audio books “borrowed” from the library have DRM encryption and a time limit (usually 2 - 3 weeks). They’ll stop working after that time, probably giving you the “synchronize” error message. You might have to re-borrow them again.