Audible on Garmin Nuvi

I have a Garmin Nuvi 650. It is old. I cannot find the Audible Manager for Mac that allows me to add books to the GPS.

I used to be able to add books to it.

I changed the SD card, so the old file structure was gone.

I downloaded the book files to my computer.

The fix was simple. Add a folder named Audible in the root of the SD card and copy the book files using Finder. I can listen to the books now.

Nuvi only recognizes .aa format, not .aax. Before downloading from Audible, select the Format4 option, which will download as .aa files.