- I've used the Relish 'dementia radio' [1] before. Its a radio with support for reading from usb, but has no memory so useless for audiobooks. Very overpriced.
- The 'National Library Service for the Blind and Print Disabled' has excellent cassette type players [2], but they only take their cartridges. Ideally something this format but supporting usb/sd card
- Another comment [3] here suggests a smartphone with a macropad. this could work. they also built a custom solution.
[1] https://relish-life.com/en-us/products/relish-radio [2] https://blog.library.in.gov/wp-content/uploads/2020/04/isl-t... [3] https://news.ycombinator.com/item?id=43818639