Wondering how this is going for you two. My '14 Overland decided to stop recognizing/reading both my USB and SD Card. It has been fine since March.
I unmounted both devices, turned the Jeep off, turned the Jeep on without the devices in, then turned the Jeep off again, then inserted the media and started. It started playing again for about 10 minutes, then I shut the car off, remote started, and nothing, once again.
Seems to me to be a radio issue as both devices failed and/or worked simultaneously.
Also, neither device is particularly loaded with songs, so I don't buy the too much memory stuff.