GMC Sierra 2005 Owner's Manual page 289

P (Power): Press this button to turn the system on or
off. The rear speakers will be muted when the power
is turned on unless your vehicle is equipped with
®
the Bose audio system.
u (Volume): Turn this knob to increase or to
decrease the volume. The left knob controls the left
headphones and the right knob controls the right
headphones.
SRC (Source): Press this button to select a source:
radio, cassette tapes, CDs, or DVDs.
x w
SEEK : When listening to FM1, FM2, or AM,
press the up or the down arrow to go to the next or to the
previous station and stay there. This function is inactive if
the front seat passengers are listening to the radio.
When a cassette tape is playing, press the up or the
down arrow to go to the next or the previous selection.
This function is inactive if the front seat passengers are
listening to a cassette tape.
When a CD is playing, press the up arrow to go to the
next track on the CD. Press the down arrow to go to the
start of the current track if more than eight seconds have
played. This function is inactive if the front seat
passengers are listening to a CD.
PROG (Program): Press this button to go to the next
preset radio station set on the pushbuttons on the
main radio. This function is inactive if the front seat
passengers are listening to the radio.
When a cassette tape is playing, press this button
to go to the other side of the tape. This function
is inactive if the front seat passengers are listening
to a cassette tape.
3-121