While a majority of the Sonic characters in the game are voiced by their 4Kids Entertainment voice actors at that time, Big the Cat and Omochao's voice clips are instead taken from Sonic Heroes and Sonic Adventure 2 respectively. These characters only appear in the DS version of the game, and since they use archival recordings, their voice actors Jon St. John and Lani Minella are credited in a separate section from the main Sega voice cast.

The music that plays during the shooting sections of the Biathlon event in the DS version is 65 seconds long, but only half of it is actually heard in-game since the player only has 30 seconds to shoot each time.