I try MP3 SHIELD on the ChipworkX_DevSys example, modify the SDI_CS (FEZ_Pin.Digital.Di2), SCI_CS (FEZ_Pin.Digital.Di9) and DREQ (FEZ_Pin.Digital.Di3), SDI_CS on the ChipworkX_DevSys (PA15/MP3_XDCS), SCI_CS (PC4/MP3_XCS) and DREQ (PC7/MP3_DREQ), no sound from the results, do not know where the error is? is it because there is no external DC adapter?
This demo already include the drivers for the MP3 decoder http://wiki.tinyclr.com/index.php?title=GHI_Graphical_Demo