USB music issues/testing

I loaded a 4 gig USB stick with about 700 mp3s. I plug it in the USB slot and select it in the mode interface. Takes 1:30 to scan the USB stick. The tracks appear and are selectable and playable initially. If I scroll through the files the interface stalls and then fails to see any files. Removing and inserting the USB stick brings the same results. All of the files are in the root of the stick. I am going to sort them into folders and see if this helps.

We have our MP3s in folders on a 16Gb stick, and it works ok. There's no way, that we know of, for the system to play the entire set randomly, but maybe if all the files were in one folder, without subfolders, you could do that.

My wife decided to get a dedicated iPod for just playing music in the i, it was an easier solution for more functions than trying to figure out how to get a memory stick to do anything other than basic folder playback.