The Mazdaspeed Protege's Kenwood Stereo, Model # KDC-MP919

The Mazdaspeed Protege has a lot of aftermarket parts, including the Kenwood stereo system.  The Kenwood unit is model number KDC-MP919 which is MP3 and Sirius Satellite Radio compatible.

Kenwood Instruction Manual (PDF)
Sirius Instruction Manual (PDF)