Oh, wow. I wonder how long that's been there. I tried every plausible keyword I could think in the help window, but never thought of "playback position" as the right term.

Looking at the help file (now that I know where to look), I see that if you designate the file as "Audiobook," it does that automatically, but I started calling my audiobooks "Books & Spoken" before that feature was added.

Thank you very much!