Continuity mistake: In the room when DJay first plays his keyboard, the dirt pattern on the door behind him changes drastically when the scene changes.
Factual error: Clyde is in the shop buying batteries for his microphones. The microphones we see later, are Shure studio microphones that do not use batteries. Batteries are very rarely used in studio microphones.
Revealing mistake: When DJ gets arrested, handcuffed and put in a police car, it's shown that he's actually holding his own cuffs.
Answer: Yes he did. The lyrics for the songs that he raps in the movie were written by the group Three Six Mafia.
Rollin Garcia Jr