Originally Posted by The Stig
Curious to know what'll happen if you try to index more than the 10,000 song limit.
My understanding is it will begin to omit those entries. I had another USB related question a while back and was able to get in touch with one of the programmers for the radio here on the forums (codeman71). The radio only has a certain amount of memory allocated to index/buffer these songs, the number of max songs (10,000) isn't a hard coded number and may rely on the size of the files.
Here is one of my earlier posts about trying to get the indexing done right. It may be a little unrelated, but still has some good information about the system.
I had a similar issue, but was able to easily solve it. I got in touch with one of the programmers for the radio (codeman71) and found out that the indexing is done when the USB device is first plugged in or if there has been any changes to the amount of data on the device (add/remove music).
As for the order of the songs, it is based on the ID3 tags of the mp3s. I was frustrated as well when a filename would be something like "Pink Floyd - Sheep", but it would either not show up or be listed under "unknown artist" on the radio. Sure enough, the ID3 tags for the mp3s were incorrect. Be sure they are all the same as well as capitalization makes a difference.
Example: Having 2 MP3s with one as "Pink Floyd" and another as "pink floyd" will make 2 separate entries for Pink Floyd on the radio.
I had an iPhone previously and it worked perfectly with the setup. I now have Android (love it), but have to use it in UMS mode to simulate a USB stick. I'm working on an app for Android to mimic the functionality of the iPhone. When the iPhone/iPod is used, the device itself is piping the music to the radio unlike the Android/USB method where the radio directly reads from the media.
Also be aware that when using a USB stick with the radio, there is around a 10,000 song limit.