Graco Pack'n'Play Owner's Manual page 24

LIGHT BUTTON— Press once for light, twice to
increased brighness, and three times to increase
brightness again. Press a fourth time to turn light
off.
VOLUME BUTTON— Press top portion of button
to increase volume and bottom portion of button
to decrease volume. There are 5 volume settings
VIBE BUTTON— Press top portion to turn vibe
on and bottom portion to turn vibe off. For steady
vibration, press power button to turn everything
off then press top portion of vibe button. Pressing
it again will turn steady vibe to low setting, bottom
portion will turn vibe off.