30 lives:
Press Up(2), Down(2), Left, Right, Left, Right, B, A, Start at the title screen. Note: To get 30 lives for player two, press Press Up(2), Down(2), Left, Right, Left, Right, B, A, Select, Start.

Sound test:
Hold A + B buttons and press Start at the title screen (with the "Start" option). The sound test menu will appear. Press B to play the music and press A to stop.