I have a 4 port USB hub plugged into the USB port. I have 4 differently named 4 Gb USB drives in the four ports each drive has 25 t0 50 songs and one has around 500 songs. Under media I can select the drive I want. This allows me to easily select what I want to listen to for short rides a the 500 song USB for longer rides. From what I understand the system will support up to five USB drives.

 

Did you figure out the continuous read problem?
I have a 2015 UC Limited and it never quits reading the drive regardless of what size drive or how many songs. I've used 2GB to 32GB drives with 50 songs or 1500 songs. Tried several different brands, sizes, jpg and wma song formats. If I go to the radio and right back to the USB media it will work properly. Also when it is in the reading mode you cannot save a song to any of the memory positions. HD has changed the USB cable and updated the software with no help.

 

[QUOTE=HotredJohn;14492996]Has anyone experienced a limitation with the number of music files on the USB drive. I think I hit a limit, previously I was using an 8 GB drive that held about 1,350 songs. When I upgraded to a 16GB drive and loaded up about 1,650 songs the radio would never stop "reading the drive".


Is there a maximum number of songs that can reside on the USB drive

My usb does the same thing. I always, turn on my acc switch first, before I start the bike,while I put on my helmet and gloves, and let it read for about a minute or two, when it stops reading I then start my bike. This seems to work.