When I read the applicable portion of the Users Guide -- among the 908(!) pages -- of my previously-owned, but new-to-me, 2013 ES350, I read with interest the feature which is the USB port inside the drivers right console/armrest. I had already used it to charge my cell phone and that worked fine. So I know there's no electrical problem. So I loaded an audiobook (about 100 MP3 tracks or 725MB) onto a 1GB USB thumb drive, plugged it in and selected USB on the selection menu on the center display. It displayed "Searching for music" momentarily and quickly began playing the first track (the book's intro). Great ... BUT ... it played about four or five tracks and then would play no more. In fact it wouldn't even go back and replay the first track. I had to remove the thumb drive and re-insert it and the entire scenario occurred once again.
Has anyone had any experience with this "alleged" feature?
(I think I'll have to burn an MP3 CD if it'll fit, but this sure seemed easier ... if it had worked!)