In the Groove Game Cheats

Avoid being locked into a song by Chance:
Normally, when you pick Chance, you are locked into the song it chooses. However, if you select the song and enter the settings menu, then back out with Triangle, you are returned to the song wheel and are no longer locked into the song chosen by Chance.

Extras:
Complete the indicated number of songs to unlock the corresponding extra:

Disconnected -Hyper song:
10 songs

Bounce marathon:
20 songs

Tell song:
30 songs

Bumpy modifier:
40 songs

Anubis song:
50 songs

Outer World marathon:
60 songs

Bubble Dancer song:
70 songs

Beat modifier:
80 songs

Disconnected -Mobius song:
90 songs

Liquid Moon song (In The Groove 2):
100 songs

Don't Promise Me ~Happiness Comes Mix~ song:
110 songs

Funk Factory song (In The Groove 2):
120 songs

DJ Party song:
130 songs

Tribal Style song (In The Groove 2):
140 songs

Infection song:
150 songs

The Legend marathon:
160 songs

Pandemonium song:
170 songs

Incognito song (In The Groove 2):
180 songs

Xuxa song:
190 songs

Wake Up song (In The Groove 2):
200 songs

Unlock All Songs:
At the title menu, press: Up, Right, Up, Right, Left, Down, Left, Down, Up, Right, Down, Left, Up, Left, Down, Right.