Joe - Thanks for your reply - On this board I have built, I have other components - a pot, an LED and a hex switch. I have been able to write snippets of code to test all of those individual items and everything works fine. The only circuitry involved with communicating with the MP3 player are 2 copper traces that go from the pic pins to the connector that the player plugs into (about 1/4" long each) - very straight forward. As I mentioned earlier, I had this working on 2 other boards that used different chips (and it still works) so it is not the player or the program. It just seems to have something to do with me using the 628. I would go back to using the 629, but I need more I/O and using the 876 is overkill. The 628 is perfect, I/O wise... I just can't figure out why it is different...