We are using Arduino Uno revision 3, with TinkerKit DMX Shield rev. 4 and Sparkfun Mp3 Shield.
We uploaded the Mp3 Shield example called FilePlayer and after we open the serial monitor, the interface is there and working. The problem is that it won't output the music from the SD card.
If we ONLY stack the Mp3 Shield onto Arduino, it works.
Is there some king od incompatibility between the DMX and Mp3 Shield, and if there is, what would be the solution, maybe some kind of bypass, since we aren't that familiar with what pins the DMX shield uses for it's purpose. ATM the Tinkerit site is down so we can't acess the TinkerKit DMX Shield datasheet.